ADVANCEDDIVER

MANUAL

ESA ® No part of this book may be reproduced in any formProduct n° M0031

Editor: Mauro Bertolini

Formative project, development, consulting and revision:Mauro Bertolini, Mario Romor, Enrico Firpo, Egidio Trainito

Text: Enrico Firpo

Illustrations: Stefano Trainito, Jacopo Pasqualotto

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IndexAn Outstanding DiverESACertification Entry RequirementsCourse StructureCertification RequirementsESA Nitrox Diver CertificationUsing the Manual

Unit OneDeep DiveWhat will you learn? Why deeper?Where should the dive take place? Types of Deep DivingHow to deal with the effects of water pressure and depth BreathlessnessOrienteeringNitrogen NarcosisDecompression sicknessOxygen toxicityAir consumptionThe Correct Diving EquipmentDive Pre-planning and Partner SystemOpen Water DiveCongratulations!What did you learn?

Unit TwoOrienteering DiveWhat will you learn? Pre-PlanningReference marks during the descentReference marks during the diveEstimating the distances Using the Compass Underwater HazardsOpen Water DiveCongratulations!What did you learn?

Unit ThreeHover diveWhat will you learn? Using your equipment correctlyAutogenous trainingDiving techniques in open water

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Checking the weight prior to a diveDescending without references Buoyancy controlAscending and carrying out the safety stop without a reference lineChecking your weight after the diveOpen Water DiveCongratulations!What did you learn?

Unit FourDiving with the computerWhat will you learn? Square and multilevel diveDive computer characteristics General rules to apply when using a computerWhen buying a dive computerOpen Water DiveCongratulations!What did you learn?

Unit FiveNight DiveWhat will you learn? Why diving by night?Pre-planningEquipment Night diving techniquesOpen Water DiveCongratulations!What did you learn?

Unit SixEcological DiveWhat will you learn? The food chainsConsumersVertebrates and Invertebrates How do invertebrates obtain their food?SymbiosisOpen Water DiveCongratulations!What did you learn?

AppendixesDive planning outlineNot to be left at home9 Rules for looking after the environment9 Safety Rules45 Questions To Remember Have you got a good memory?

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An OutstandingDiver!Travelling along the southern coast of France onecan admire an unforgettable panorama: an incre-dible display of bays, gorges and headlands one afterthe other.While driving you are surrounded by an amazingview, but this does not stop you from wanting to dis-cover what is behind the next curve, even if what youare already experiencing is exceptional and satisf-ying. Man has always been inclined andcurious towards adventure and disco-very.Surly, you must have already askedyourself what new things you could dosoon after getting your licence andhaving had your first diving experien-ces. It might have already happened toyou not to be able to dive from a parti-cular spot because considered suitableonly for expert divers due to its charac-teristics, and perhaps at the time youmight have been resentful towards theguide for not having allowed you toparticipate. But you must have alsounderstood that the guide is a profes-sional diver, who will not take youunderwater only to have an extracustomer on the boat.The knowledge and the techniques thatyou have learnt in your previous cour-se are necessary to allow you to dive insafety and within the recreationaldepth limits. In order for you to gobeyond and discover what is in yourdiving future you must get more infor-mation and learn new diving techni-ques, only after you have done all this,you’ll be able to enjoy fully your diving adventures,taking safety always into consideration.The new course that you are about to begin willteach you new theoretical knowledge and divingtechniques that will expand your experience and willenable you to become more independent and safeunderwater, under the supervision of your ESA

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instructor.Along the channel between Sicily and Calabria thereis a beautiful diving spot where you can find avariety of red and yellow sea fan, to see them one hasto descend to a depth of 18 meters. As you learnt inthe previous course, to be able to do so, it is impor-tant to know the correct techniques in order to pre-vent eventual problems. Another exciting experience that you can have inthis area is to encounter the Mediterranean trumpetfish. Would you like to see him? It’s easy, all youhave to do is go night diving! Are you scared? No, because during this course youwill learn all the techniques that will allow you to go

night diving safely, making the mostof the incredible scenery that willsurround you.This course will give you loads ofopportunities and at the end you willfeel like an out of the ordinary diver!Ask ESA’s professionally qualifiedteam for more information anddon’t hesitate to dive into this impor-tant and fascinating adventure.Tuffati subito in questa importanteed affascinante avventura! -

ESAESA is an international scuba trai-ning agency, its objective is to formthe divers, following them throu-ghout their training, from beginnerslevel to becoming a professionaldiver, such as a Dive leader orInstructor. To do so, ESA uses themost advanced teaching techniquesand promotes all aspects of this acti-vity, giving a very high priority tosafety.ESA courses provide first classtheory knowledge, given by theInstructor, who will give you all thenecessary information throughout

the training. The practical knowledge will be car-ried out in a swimming pool or a delimited waterbasin, where you will learn all the diving skills thatyou will subsequently apply and improve in openwater.At the end of every ESA course, the instructor willverify the learning progress of the divers. ESA will

Let’s jumpinside thisfascinatingadventure

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train and follow the divers throughout the variousphases, from beginners level all the way to beco-ming a professional diver or specialising in variousactivities such as marine biology, marine archaeo-logy and photography, etc.ESA sets very high standards for its instructors:These are professional divers who hold an ESADiveleader certificate or higher certificate.ESA Instructors have a complete knowledge of thediving world that has been passed on to them by theESA IC Directors, which are highly qualified divers.The ESA diving certificate will be validated directlyby ESA headquarters or by one of the authorisedESA offices. The department that deals with the for-mation of the students will inform all theESA affiliates about any new or changedprocedure. All those structures that alreadyprovide diving facilities can become an ESAaffiliate, while diving clubs or scuba divingretailers can become ESA points. All ESAIC Points can organise and promote divingcourses for ESA Instructors.To improve the quality of this activity andthe knowledge of the underwater world,ESA gives a high priority to the environ-ment by trying to make the divers moreaware of their surroundings.Throughout their formation, ESA professio-nals receive a solid background about theenvironment and its conservation.

CertificationThe Advanced Diver is the second level ofthe ESA diver educational system. Itmeans that you have successfully comple-ted all the steps leading to this course andthat you are now ready to access most ofthe ESA specialisation courses and canmove towards the ESA Prevention andRescue Diver certificate. This also meansthat you have good credentials as a relia-ble dive partner, even for those divers thatyou will meet for the first time during oneof the ESA club/points diving excursions. Thiscourse will also emphasise your future aspirations,you could indeed discover a special interesttowards one or more activities and decide to spe-cialise with one of the ESA Specialisation courses.

Entry Requirements

You candiscoveryour preferreddiving activities

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To be admitted to the ESA Advanced Divers courseyou will need to meet the following:• Obtain the ESA Open Water Diver certification orcomparable• Physically fit for diving• Should be 15 years old or older• Submit a valid medical certificateTo be admitted to the Junior ESA Advances Divercourse you will need to meet the following:• Obtain the Junior ESA Open Water Diver certifica-tion or comparable• Physically fit for diving• Should be 12 years old or older• Submit a valid medical certificateIf you have any doubts or questions about the requi-rements please do not hesitate to ask clarifications atone of our ESA points or directly to the ESAInstructor.

Course StructureESA has structured this course in a flexible way tomeet the needs of the students and the instructor,taking into consideration a suitable timetable and

environmental conditions, to make all thevarious phases of this course accessible.The course is divided as follows: 1) Theory Section, and 2) Open water dives

1) The Theory Section consists of the infor-mation that you will find in this manual, youcan test your knowledge by completing themini tests and questionnaire that you willfind at the end of each unit. The instructorwill also give various presentations and willintroduce you to the open water dives byshowing you the ESA advanced Diver video.

2) The Open Water Diving section will bedivided in the following: 1. Deep Diving2. Orienteering Dive3. Hover dive

4. Computer dive5. Night Dive6. Ecological Dive 1,2,3 and 4 are compulsory dives, dive 5 can beexchanged with dive 6 according to logistics, safetyor for local rules and regulations. Before each dive there will be a theory section and

A diversignaling“OK” to herdive partneron boat

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a pre-dive briefing. If you still do not have yourown equipment you will be issued with the neces-sary equipment.

Certificate RequirementsWhat do I need to do to obtain my certification?To obtain your certificate you need to complete theAdvance Diver course, show that you are familiarwith all the various aspects of this course and thatyou have successfully met your targets. The way the Advanced Diver has been structuredwill help you to tailor this course according to yourneeds, for example, ESA enables you to start thiscourse and then finish it at a later date, even withanother diving school, to avoid starting from thebeginning. What is important is to complete all thevarious sections of this course, only after havingpast the last required dive the instructor will issueyou with your diving certificate, you will not be ableto obtain your certificate until you have completedall your dives. Please note that you will need to pass one divebefore moving on to the next one, your instructorwill advise you on the best ways ofobtaining your certificate.

The certification will be hand outdirectly by the instructor.This will enable you to take partimmediately in scuba diving trips,other courses and dives, and to rentdiving equipment. Please remember that your certifica-tion is subject to a time restriction.Before the expiry date you will recei-ve in the mail a sticker that will per-manently validate your certification. If you do not receive your sticker bythe expiry date of you certificationplease do not hesitate to contact oneof the ESA offices, our staff will behappy to help you.

ESA Nitrox Diver CertificationIf during your programme you will useNitrox on two occasions and if youhave already had a theory session, youare entitled to apply for the ESA NitroxDiver Certification, ask your instructor or a ESAPoint how to enrol on the course.

If you havenot yourpersonalscubaequipment,you willreceive allthe coursestandard requiredi-tems

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Using the ManualThis manual will become an essential tool for yourdiving career! If you haven’t been in the water forsome time you can refresh your memory by flickingthrough the pages. If you decide to pursue thiscareer and become a professional diver you will findthis manual very useful even during the ESAPrevention and Rescue, Dive leader or even duringthe ESA IC courses. The text of this manual is veryeasy going to facilitate the learning process, each unitis divided into subjects, a mini test will highlight the

important things to remember, and aquestionnaire at the end of each unitwill help you keep track of your kno-wledge. Also, each unit contains thediving instructions, showing you theexercise that you will need to comple-te during your next dive.

Remember to bring your manual toyour next lesson. Take notes and askyour instructor for clarifications.

The manualwill be veryhelpful both during andafter thecourse

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Unit OneDeep Dive

What will you learn? The good thing about nature documentaries isthat they broadcast a mixture of images, scienti-fic information, mystery and adventure. Thecameramen that shoot the footage for thesedocumentaries most likely must be very gooddivers, taking into consideration the amount ofheavy equipment that they take underwater withthem – cameras, batteries, lights, etc. Thanks tothese cameramen we can have an idea to whatit must be like to swim with sharks, turtles, seasnakes, a school of big eyed jackfish, napoleonfish wrasse, groupers or even the funny hermitcrabs. Through these documentaries we learnabout the life and habitat of these fish and mari-ne organisms, but we never hear about howthese images were taken and at what depth thecameraman has to descend to be able to encoun-ter these creatures. It is true that these docu-mentaries are not meant to be related to diving,but for a diver understanding the depth of thewater is extremely important no matter whattype of dive you are planning. Whether you arestill diving in shallow waters or if you are readyto explore deeper waters and new habitats. Theconditions of a dive can vary drastically depen-ding on the depth of the water, in this unit wewill learn all the aspects of deep diving, startingfrom the simple questions that a diver must askhimself before diving in deep waters – Why?Where? How? When?You will learn the main factors that you need toconsider during your dive and how to deal withany situation. You will familiarise yourself withthe correct techniques and the equipment usedwhen descending to a depth of 30 meters. Thetheory section in this unit will give you all theinformation you need when deep diving. Beforethe next lesson read the unit and complete themini test and questionnaire, this way you will beable to put the theory into practice!

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Why deeper?

What would you answer if asked? You would pro-bably list various reasons, but the first words thatmight come into your head are adventure and dis-covery. These are two exciting aspects of this course, butyou also need to concentrate on other important fac-tors, to avoid being disappointed.No matter what type of dive, pre-planning is essen-tial. The first question you must ask yourself when plan-ning a dive is “Why deeper?”

The deeper you go the more oxygenyou consume, therefore you willhave less time to stay underwater.In spite of this time restraint diversstill enjoy and find deep divingsatisfying. Lets take a step back-ward and lets ask ourselves a diffe-rent question:

“What will I encounter at 18-20meters?

At what depth do I need to descendto observe the red and yellow seafans, the stove-pipe and vase spon-ges?

At what depth are the ship wrecksfound?”

Usually to be able to see thesethings it is necessary to dive deeperthan usual. If you follow all theinstructions and apply the correcttechniques as shown in this courseyou will become a keen diver. With the new ESA Deep Divercourse you will be able to learneverything you need to know aboutdeep diving and you will fulfil yoursense of adventure, but most of all itwill make you aware of your limits,

the importance of equipment maintenance, the needto pre-plan and the need to create a good partnersystem while diving, this should never be neglected.

Divers cansee this wonderfulgorgoniasfrom a depthof 25 – 30

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Where should the dive take place?

Types of Deep DivingAfter obtaining your ESA Advanced Diver certifica-tion you can try all the various types of deep divingand you will probably find that you will becomemore inclined towards one method in particular.You might decide to travel and visit the tropicalcoral reefs or you might decide to stay in theMediterranean, considered by many to be fascina-ting and mysterious. No matter where you decideto go each dive will be different, each diving sitewill vary according to its characteristics. Evenduring this course your instructor will select thediving sites taking into consideration the logisticsand naturalistic interests.

Diving along a wall or a sloping shoreBy anchoring the boat near a wall or a reef thatdescends vertically into the sea, sometime even forhundreds of meters (don’t worry you will notdescend that deep!), it is possible to dive and explo-re the surroundings. Some islands are suitable for this typeof diving. Sometimes it is necessary to swim onthe water surface for a short distance,as it is not always possible to get tooclose with the boat. Plan this aspect in advance, otherwiseyou will end up being tired even befo-re diving. Also, remember to arrangefor qualified assistance on the boat incase of an emergency. The nice thing about diving along awall is that you can descend andascend, carrying out your safety stopwithout missing out on the surroun-dings. To maintain a comfortable position,for example when exploring a wall,good buoyancy is important. If you think that you still need to prac-tice you’re buoyancy control, ask your instructor tolet you carry out your hover dive first, which is partof this course, and then move on to the other dives. Deep diving can also be practiced by entering thewater from the shore, you should calculate howlong it will take you to reach the required depth,usually the shore slopes gradually and it might be

A dive teamcheckduring adeep dive

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quite a way before you find yourself in deep water.Wrecks and sholesDuring a wreck dive it is necessary to descend fol-lowing the anchor line or a reference line, what youwill see while descending will be breathtaking. Atthe beginning, depending on the visibility, youmight not be able to see further than the hand hol-ding the reel, but as your eyes adjust you will startto see rounded shapes and high pinnacles, slowlythe wreck will unfold before you. Usually it will take a few dives to be able to see theentire site. This will give you the chance to plan your routes inadvance, each time seeing the wreck from a diffe-rent angle. Having a good sense of orientation is fundamentalto be able to re-surface when needed, you shouldalways keep an eye on the air reserve indicator.Don’t worry: during the orientation dive, which ispart of this course, you will learn to use referencesto find your way back to the shore or the boat whenneeded.

Do you find wrecks fascinating? Most of these wrecks are found at a depth of 20meters or more. If you are planning to visit thesesites, it is advisable to learn to dive and what betteroccasion than to attend the ESA course specialisedin wrecks. Ask your ESA instructor for information.

How to deal with the effects of waterpressure and depth We now have a picture on the various types of deepdiving, remember that the same rules apply for wha-tever type of dive. Water is very different from air, it is 800 times den-ser than air, to dive you need to adapt completelyto this new environment, in order not to be affectedby the increase of pressure you need to learn howto move and breath correctly in the water. When diving with the scuba equipment your actionswill be affected by the depth and therefore by thepressure of the water, you need to learn how to dealwith any situation, for example the breathlessness

BreathlessnessWho hasn’t been out of breath at lest once? A strong

Minitest1. As part of this courseyou will learn the safetytechniques:a. Beyond the recreatio-nal dive limitsb. Within the recreationaldive limitsc. Beyond 40 meters ofdepth

2. The deep dive pre-planning should include:a. Observation of parti-coular marine organismsb. Diving very deep towin ones fearsc. a and b are both cor-rect

3. A diver should learnthe deep dive techniquesto:a. Be able to dive on hisownb. To be aware of oneslimitsc. Know how to survive

Answers 1b – 2 a – 3b

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emotion, a constriction or a physical strain caneasily trigger this reaction. The dictionary defines it as a shortness of breath orlack of air. Already in your first diving course youmust have learnt what to do if you find yourselfbreathless.

Even during the Open Water Diver course, which ismainly undertaken in shallow water, not deeperthan 18 meters, the diver is warned about the risksof breathlessness and learns how do move andbreath correctly to prevent it, all the more reasonwhy this should be taken into consideration whendeep diving.

The density of the air breathed at 30meters is twice as thick as the air brea-thed at 10 meters, reaching 4 bar, thismay cause the diver to gasp. To have a good diving experience,without stress and discomfort, youshould learn how to preventbreathlessness.

The diver who wants to deep diveshould be fit, should have the rightequipment and obviously shouldknow how to breath and move cor-rectly. When planning a dive speak toyour dive partner. If you feel uncom-fortable, you should not be forced intoa stressful situation as this might causeyou to feel breathless. This reaction could also be caused byfaulty equipment. You should very carefully select yourregulator according to its performance. During this dive you will notice thatthe instructor will stay close to youand will often signal “OK” to you.Respond promptly to his signals. During future dives with your divepartner remember what you havelearnt, practice signalling to each other, monitoringyour breathing. If you start gasping remember to move slowly and

to respect your limits, if you feel like you are notgetting enough air, stop, take a deep breath, findsomething to lean against and signal to yourdive partner.

A diverbreathles-sness situation.This mayeasilyappenduring adwwp divedue to theincreasedair density

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OrienteeringThe deeper the water the less light and visibility youhave. You will not find yourself suddenly in thedark, but the murky water will disorientate you andyou will not be able see the references that you nor-mally use to find your way. During many occasions you will be able to divewithout references, but in a deep dive you shouldalways have a reference mark, such as the referen-ce line, a wall or a sloping shore. You should always stay close to your dive partner,without losing sight of each other.When descending look around and focalise onyour references.

If there are no natural refe-rence marks, look at yourdepth gauge, your divepartner, the reference lineor even towards the watersurface. Once you arrive at the desi-red depth you have twochoices: if the visibility isgood you can explore yoursurroundings staying closeto your dive partner, but ifthe visibility is not so goodyou could explore the vici-nity without loosing sight ofthe reel. During a deep dive it is bet-ter not to swim too far fromthe rope, not only for thereduced visibility, but alsofor the increased consump-tion of oxygen. You will learn how to findyour way underwaterduring the orientation dive,which is part of the course. Many decide to dive bysigning up to a divingschool. A guided dive

should be taken into consideration when diving in anew place, especially if deep diving. Ask an ESA point information regarding an areawhere you would like to dive, you will find that ESAis also highly qualified for guided dives.

To better pre-vent anykind of pro-blem, duringthe deep diveit is necessary toimprove thedive teamprocedures

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Nitrogen NarcosisDuring the Open Water Diver Course you havelearnt about nitrogen narcosis. Nitrogen narcosis isa depth related condition that starts to occur atabout 30 meters and it increases with increasingdepth. Some divers experience no narcotic effectwhereas others already feel some effect even inshallow waters. Start to descend very slowly.As you already know this will help to adapt to theeffects of the pressure and it will give you a chanceto get your bearings, but also this is to prevent suf-fering from nitrogen narcosis. You should stopimmediately if you start feeling light headed orgiddy, the symptoms will stop as soon as the diverstarts to ascend. Nitrogen narcosis manifests itself by giving the divera off balance, drunken feeling. The diver will notalways realise to be suffering from narcotic effectand this is when diving in couples becomes veryuseful. It is easy to help your dive partner shouldyou notice an unusual behaviour, all you need to dois signal to ascend. As you have probably noticed,there are no particular exercises that you need tolearn before deep diving, all you need to do is pre-plan your dive applying the common diving rulesthat you already know so well, using the correctequipment and keeping an eye on the effects ofdepth. The ESA staff will guide you and will make yourdeep diving experience one to remember. It is important, when you are underwater to makesure that your senses are sharp, as we have alreadysaid the nitrogen will slow down your reactions andcloud your judgement, the instructor will teach youa few simple mental and manual exercises, such ascounting your fingers or solving a simple mathema-tical problem on your dive slate.Decompression sicknessYou have already learnt about decompression sick-ness during your first course. Inevitably the tissue of our body will absorb a cer-tain amount of nitrogen in relation to the depth andtime spent underwater. This means that the longer and the deeper youdive the larger amount of nitrogen we absorb.You have probably noticed by looking at your divetable that the deeper the dive the less time you willspend underwater, this is to keep monitor and limitthe amount of nitrogen, to enable the diver to

Minitest1. When deep diving a fewfactors are …………… andshould be…………….:a. Unknown – left to sortout themselvesb. Amplified by the depth ofthe water – taken into consi-deration and solved with theappropriate techniquesc. Amplified by the depth ofthe water – ignored

2. True or False.During a deep dive a divershould prevent feeling outof breath, as it is an out ofcontrol situation.

3. When deep diving it isbetter to ……………., thiswill facilitate ……………:a. Descend following a refe-rence – the divers’ underwa-ter orientationb. Descend using a reel –the divers movementsc. Descend only along awall – the divers’ underwa-ter orientation

Answers: 1b 2 True - 3a

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ascend without having to make decompressionstops. This applies to deep diving, when pre-planningyour dive choose a depth that does not exceed 40meters and keep in the decompression limits. Youwill find all the information you need to pre-planthe dive on your dive table and your computer. The computer will provide you with on the spotinformation, such as to the remaining time, whichvaries depending on the depth.

If you still haven’t tried diving with the compu-ter you will be able to do so as part of this cour-

se.

There is no fixed rule concerning the intake ofnitrogen as it varies for each diver. The dive tableand the computer give a wide margin of safety,but cannot guarantee that a diver will never expe-rience of decompression sickness symptoms. The nitrogen is released when the pressuredecreases, in other words when ascending, and itcontinues to be released even after re-surfacing. To reduce the risks and to get rid of the nitrogenthe diver needs to follow all the rules and proce-dures with care, which are: respect the no decom-pression dive limit, ascend very slowly (at least 10meters per minute), and before re-surfacing (5meters below the surface) carry out a 3 minutesafety stop. As you probably know the safety stop is not acompulsory requirement, but a diver shouldalways carry out a safety stop when deep diving. When deep diving you are also advised to reducephysical strain and the exposure to the cold,which both increase the nitrogen concentration inthe body tissues, therefore decompression sick-ness. Even after the dive, on the boat or the shore,limit physical strains and before moving to an alti-tude (even by car) wait at least 24 hours. Do you remember how decompression sicknessoccurs? Nitrogen bubbles form in the body tissues,

the symptom and consequences will vary accordingto the number and location of these bubbles. If abubble forms near a joint you will feel pain and youwill not be able to move the affected limb, a bubblein the spinal cord means that you could becomeparalysed. Pure oxygen should be given if any decompression

A dive com-puter.During thecourse youwill carryout a divewith thecompure

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sickness symptoms occur. Ask your instructor, hewill be happy to show you the oxygen kit that hemost likely will have.Oxygen toxicityOxygen, like nitrogen, can cause problems at adepth. The symptoms can be severe, such as convulsionsor sudden loss of consciousness, but this type ofconsequence usually only occurs at a depth of 60meters, so why worry? As you know the recreational depth limit is 40meters. During this course, under the supervision of yourinstructor, you will descend to 30 meters, well abovethe danger limits. All divers mustlearn about the danger of oxygentoxicity, the rule that applies for deepdiving, as well as every other dive, isto pre-plan your dive and keep well inthe recreational depth limits!

Air consumptionAs you know by now, at 10 meters ofdepth you will consume twice asmuch air as you would on the surface.You need to consider this carefullywhen diving.

How do you manage your air?When deep diving you need to checkyour pressure gauge and signal toyour dive partner often to avoid run-ning out of air during your safety stop,keeping in mind that the ascent for adeep dive will take longer.

The ascent speed should notexceed 10 meters per minute, thismeans that if you are ascending from30 meters you will take 3 minutesbefore you reach your safety stop (tobe on the safe side we have kept awide margin!). In any case, the air consumptionvaries according to each diver, when the dives aredeeper it can be wise to use a cylinder with a largerair capacity. So remember: Check your pressuregauge regularly, signal often to your dive partner,and allow for your safety stop. In an emergency,should you run out of air before your 5 meter safety

1Two diversduring thesafety stop

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stop, a small cylinder (two people can use it) can beused. Most of the time the boat used for these diveswill have a metal bar provided with one of thesesmall cylinders hanging in the water, the divers canhold on to this bar during their safety stop. Duringyour pre-diving briefing, the instructor will explainthe procedures to be used during your safety stopand the usage of this safety cylinder.

The Correct Diving Equipment If you still haven’t bought your own equipment, thedive leader will provide you with the necessaryequipment during this course. Keep in mind that isbetter to have your own equipment. You need tochoose a good regulator and you need to have goodinsulation, as the temperature of the water can varydrastically, choose your wet suit accordingly. Youshould also have a pressure gauge, to measuredepth and time if you do not intend to use a depthgauge. The integrate instruments used along with adive compuper may be the best solution to assure a

complete monitoring of the dive. Your jacket should be well positionedand have a good weight system. Yourfins should not be too hard and yourmask should adhere well to your face.Do not try new equipment during adeep dive, as this might ruin yourdive, test it previously in shallowwater. A torch is a very useful piece ofequipment.Colours underwater loose their light,with a torch you will be able to admi-re their real colour. Sea fans will lookblue instead of red, a wall will seemdull and cannot be admired if themany sponges and organisms are invi-sible. The instructor will bring along atorch and you will see how this willadd value to your deep dive.

Remember that keeping your equipment in goodcondition is extremely important. With your divepartner you will need to check each other’s equip-ment before diving.

The divetorch willpermit youto discoverthe amazingcolours ofthe deep

Alwayscheck theequipment

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Dive Planning and Partner SystemWe have already mentioned various times theimportance of pre-planning your dive and theimportance of the partner system. Also, you shouldunderstand that these aspects are even more impor-tant during a deep dive. Lets go over the mainpoints to remember and how they should be carriedout:

• Pre-plan your dive with your dive partner andset your targets – remember to enjoy yourself insafety!

• Keep in the recreational depth limits – don’t gobelow the depth limit you have planned anddefinitely not below the recreational depth limits

• Always use the appropriate equipment thathas been tested and checked in advance

• With the help of your dive partner check yourequipment before each dive

• Prevent nitrogen narcosis by descendingslowly and signalling “OK” to your dive partner

• Prevent breathlessness by moving and brea-thing slowly helping each other should anysymptom arise

• Remain at a constant depth and never loosesight of your dive partner

• Check your pressure gauge frequently – moni-tor your air supply and signal to your dive partner,remember to leave enough air for your ascent

• Prevent decompression sickness by respectingthe no decompression dive limit, ascending veryslowly, 10 meters per minute and before re-surfa-cing, 5 meters below the surface, carry out a 3minute safety stop

• After re-surfacing limit physical strains and befo-re moving to an altitude (even by car) wait at least24 hours.

Minitest1. Descending slowly willhelp you to determine:a. The effects of equali-sationb. The effects of nitro-gen narcosisc. The effects of decom-pression sickness

2. The decompressionsickness is a severe medi-cal condition caused by:a. Holding ones breathand ascending tooquicklyb. Exceeding the divetable limits and withoutequalise themc. Exceeding the divetable limits and ascen-ding too quickly

3. Oxygen is a gas thatcauses problems at cer-tain depths. These pro-blems can be avoided:a. Keeping within therecreational dive limitsb. Never exceeding 18meters of depthc. Breathing a gas mix-ture that doesn’t containoxygen

Answers 1b – 2c – 3a1

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Open Water DiveDeep

BriefingPay attention to the description of each activity,asking questions when necessary.The pre-diving briefing is very important as onceunderwater it is not possible to ascent every timeyou need a clarification. The instructor will explainwhat, when and how to carry out the activities.Don’t hesitate to ask your instructor or dive leaderany questions, they will be happy to help you.

Pre-planning, wearing and checking the equipmentPrepare all the necessary equipment for thedive. With the help of your dive partner, whenputting on your equipment, carry out an equip-ment check. The equipment might vary depending on the boatused dive off, and it can be put on in or out of thewater. The equipment check should be carried outcarefully, any problem should be reported to yourinstructor or dive leader.

Entering the waterEnter the water with the correct technique sui-ted for the type of dive.The instructor or dive leader will instruct you on thecorrect technique for entering the water accordingyou the logistics and the type of boat involved.

DescentDescend using a reference line and keep within the30 meter limit. Descend checking your buoyancy, adjust yourdescent rate with your jacket and stop in neu-tral buoyancy before touching the bottom orreaching your 30 meter limit. The descent is a very important phase of your dive,you should be able to stop when needed as it mightbe useful for your equalisation should any nitrogennarcosis symptom arise. You will pre-plan the divewith your instructor. While descending monitoryour depth gauge and signal when you reach thedesired depth.

Underwater tour, instruments check and use of thesignalsAt depth, practice monitoring time left, depth

You canwear theequipmentboth onland or inthe water

Descendingalong therope lineclose to thepartner

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and air supply and signal to dive partnerand/or to the instructor

Nitrogen check: look out for the narcosis effectsWhen you reach the depth required carry out apsychomotor exercise, as shown by the instruc-tor.This exercise is useful to check if the nitrogen isaffecting you during your deep dive.

Ascent and safety stopAscend slowly along the reference line (nofaster than 10 meters per minute) and carry outyour safety stop for 3 minutes.It is important to ascend slowly and tocarry out the safety stop. The bodywill have a chance to eliminate mostof the nitrogen avoiding decompres-sion sickness. The instructor willshow how the safety stop should becarried out.

ExitExit the water following the tech-niques suggested by the instructor.

Taking off and checking the equip-mentTake off your equipment and carryout the necessary maintenancebefore storing it.During your pre-dive planning chooseequipment that is appropriate and ingood condition. The equipmentshould always be rinsed in freshwater before being stored away.

DebriefingPay attention and listen carefullyto all the instructions, recommen-dations and suggestions during thedebriefing, don’t hesitate to askquestions and clarifications.

Dive validationInsert the details of your dive in your logbookand have it signed by the instructor.To validate your dives insert all the details in yourlogbook, such as conditions, temperature and per-sonal comments. Don’t forget to have it signed by

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y o u rinstruc-tor, andask ifthere area n ys t a m p sor spe-cial stic-k e r savailableto stickon yourbook.

Congratulations!Reading this unit you probably have noticed that thedeep diving is not so different from other types ofdives. To be able to encounter certain organismsand to visit particular diving sites within the appro-ved depth limit you need to have a positive attitudeand to increase the safety rules that you alreadyknow well. When pre-planning your dive considerthe effects of deep water pressure and plan to alwaysuse the appropriate equipment. Follow some usefultips, such as taking a torch underwater and to useequipment already tested during other dives.Together with your dive partner you are now readyto explore the underwater world!

Minitest1. A diver diving at 30meters of depth uses……….. the amount ofair than ………..:a. Double – when he isat 10 meters of depthb. 4 times – when he ison the surfacec. a and b are both cor-rect

2. The most importantrule when using the airsupply is:a. Checking the pressuregauge and signalling toyour dive partnerb. Leaving enough airfor the ascent and thesafety stopc. a and b are both cor-rect

3. True or False.It is better not to try outnew equipment during adeep dive

4. The dive pre-plan-ning and the partnersystem is very importantfor every type of dive,but when deep diving itis better to:a. Reinforce the pre-planning ruleb. Reinforce the divepartner system rulec. Reinforce both rules

Answers 1c – 2c – 3 True – 4c

Do notforget tolog andvalidateyour dive

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What did youlearn?The purpose of this exercise is to go over what youhave learnt and to be sure of your readiness to moveon to the next unit. Complete the multiple choiceand hand it to your instructor, he will give you thenecessary clarifications, if needed.

1) A diver should consider a deep dive an occasionto:a. go beyond the recreational depth limits;b. visit a particular diving site;c. Encounter organisms that live below a cer-tain depth;d. Both b and c

2) To avoid the effects of depth pressure you needto:a. Pre-plan the solutions to problems causedby depth pressureb. Pre-plan the correct techniques to dealwith pressure at depthc. Be physically fit to be able to overcome thepressure at depth problemsd. Both a and b

3) True or False. All divers should know thatbreathlessness is a normal condition whendeep diving and should be fit enough toovercome it.

4) As the depth increases light and visibility decrea-se, you should:a. Plan very long divesb. Plan shorter divesc. Plan a night dived. Both a and c

5) Nitrogen Narcosis can manifest itself with slight

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symptoms which are not always perceived bythe diver, these symptoms are:a. Sudden convulsionsb. Loss of consciousnessc. Reactions are slowed downd. smaller air consumption

6) The best ways to avoid decompression sicknessare:a. Never arrive to the no decompression divelimitb. Ascent at a 10 meters per minute speedc. The diver should not hold his breathduring his ascentd. Both a and b

7) True or False. A diver doesn’t need to know theeffect of oxygen breathed at depth, as it isonly toxic below 60 meter.

8) When deep diving which of these factors need tobe considered:a. Bubbles in the body tissuesb. Air consumptionc. Visibilityd. Both b and c

9) Using a torch underwater enables you to:a. Improve the quality of your diveb. See properly after sun setc. See the colours that otherwise are absor-bed by the depth of the waterd. Both a and c

10) As part of the ESA Advanced Diver you will diveto a maximum depth of:a. 25 metersb. 30 metersc. 40 metersd. 22 meters

I declare that I have gone over all my answers withthe instructor and that I have understood all the cla-rifications given to me.

Signature_____________________ Date___________

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Unit TwoOrienteering Dive

What will you learn?

If you have been on holiday you might have alsobeen on a guided tour. Many tourist attractionlocations organise 1 or 2 days guided tours,there are excursions and itineraries to suiteverybody. Usually the itineraries are signposted for orienteering purposes. While you are admiring the scenery you canalso keep track of the distance covered by chec-king these signs, and if you want to be reallyprecise you can even try counting your steps.Divers go on underwater guided tours. The same orienteering rules apply, even forunderwater itineraries it is important to esti-mate the distances covered based on the airsupply and the time needed to go to and fromthe boat or the shore. In this case the endu-rance is calculated according to the amount ofair in the cylinderss. Orientation is essential underwater, once thediver has learnt all the basic diving techni-ques, all that is needed is a little practice to getfamiliarised with this new environment. It isalso important to be prepared for every even-tuality, for example sudden weather change,the currents and the waves. Also, the boattraffic needs to be taken into consideration.During this dive you will start to familiariseyourself with the surroundings and to applythe techniques that will make your dive funand a relaxing experience.

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Dive Planning

During the Open Water Diver Course you havelearnt to pre-plan your dive. You will rememberthat the first thing to do is to choose a suitablediving site and the best way to learn to do so is to

have a guided dive, this will giveyou an idea of what kind of refe-rence marks you should be lookingfor in future dives. Usually whendiving off shore you will find thatthe depth level slopes graduallytowards the bed of the ocean andthis will facilitate your ascent. Whendiving along a wall you will beable to dive directly off the boat andfollow the natural references oreven use a compass. We will speakabout this in the next few para-graphs. You will be able to find inthe libraries or in the local divingcentres detailed brochures withmaps and information on particulardiving sites. They will provideinformation such as the seasonal cli-mate condition, how to reach thesite, where to anchor the boataccording to the local laws, sug-gested diving itineraries and eventhe local marine fauna. If the con-ditions are favourable you even mayalso be able to find out details ofthe sea bottom. The visibility andthe natural references can vary

according to the type of sea bottom, for examplediving where there is a sandy sea bottom, withoutreference marks, can interfere with your orientation.

Reference marks during the descentThe natural surface references will give you an ideaon what to expect underwater. As a matter of factthe characteristics found on the surface reflect whatyou will find underwater, for example you willexpect a vertical wall when a sheer reef falls into thesea, while when diving from a flat island you willprobably need to go quite a way out to sea beforereaching even the depth of 10 meters. It is notvery convenient to move to far from the divingpoint. Why go far when you can also have fun near

Evaluationof the divesite conditionbefore a dive from the shore

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the shore? Usually, on sandy floors the motion of the wavescreates horizontal ripple marks, these are usefulwhen you are underwater as all you need to do isfollow the direction of the ripples (i.e. when divingfrom the shore).

Diving from a boat can be different according tothe site and the environmental conditions: Whendiving from an mooring boat you will be able to usethe anchor line as your reference line, you don’tnecessary need to hold on to it, but you can use itas a reference. After checking your equipment anddiving off the boat, look towards the bottom andstart exploring your surroundings, descend slowlywith your fins pointing downwards to help theequalisation and to get your bearings focalising ona particular rock or mark on the sea bottom. Before leaving the security of the anchor line checkyour computer or depth gauge to have an idea atwhat depth you are this will help you when it willbe time to ascend. When diving from a boat that is not anchored(where local law do not permit it or where there isa strong current) you will need to concentrate onyour surroundings as there will not always be a refe-rence mark to help you find your bearings. Whendiving in a place where there is a strong current it isnecessary to have a very good visibility, most divingcentres will be equipped for this type of condition.

Listen carefully to the briefing, once in the waterstay close to your dive partner and the guide. It isadvisable to practice your orientation skills evenafter completing the ESA Advanced Diver Course,maybe taking the ESA Orienteering Course.

Reference marks during the diveBefore leaving the reference line and after havingfound the depth, you need to decide in which direc-tion you want to go. Even in this case we havevarious options.Diving along a wall you will have a natural refe-rence to follow, you dive along the wall and onceyou have reached the desired depth you will be ableto move left and right. You will learn how to cal-culate distances underwater, which is very importantin order to be able to plan the length of your under-water trip. Sometimes a wall will drop for 7-8meters and then gradually descend towards the bot-

Minitest1. A good method tofamiliarises with a divingsite is:a. Carry out a longexploration diveb. Join a guided dive ofthe locationc. Dive various time inthe same site

2. For a good orienta-tion when pre-planninga dive you should:a. Be familiar with thetypology of thesea/ocean bedb. Be familiar with thedifferent organismsc. a and b are correct

3. A good method toknow what the divingsite is like is:a. Explore the site freedivingb. Consult a book aboutthe local diving sitesc. If available consultthe pilot’s book (porto-lano)

Answers 1b – 2 a – 3b

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tom with big natural steps. This means that to beable to dive at a depth of 20 meters you will needto go quite a way out, in this case you might deci-de to dive from a boat, descending along a refe-rence line directly above the desired depth. Even if you cannot see the wall from the place youare diving, you can use a compass to find your way.

Once you have familiarised with a particulardiving site you will be able to use only the natu-ral references.

After having swam parallel to thewall make a 90º turn and swimtowards it. If you make another 90ºturn and swim parallel to the wallagain in the opposite direction youwill have completed a rectangularpattern. A reef is a rocky formationthat raises from the bottom towardsthe surface. Sometimes you justneed to descend a few meters toexplore a reef, in other occasionyou might need to descend even 30meters to reach a reef. When pre-planning a dive alwayskeep into consideration yourexperience and the level of yourdiving certification. If the morphology of the reef per-mits it you might be able to circum-navigate the reef without having toturn around. Should the reef be toobig to circumnavigate you mightchoose to divide the reef into sec-tion to be explored in differentoccasions. As it is not possible to learn all thereis to know in just one dive, we

recommend the ESA OrienteeringDiverSpeciality Course, you will learn all the differentorienteering techniques.

A diversignalingthe direction

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Estimating the distancesPre-plan an underwater itinerary calculating accura-tely the ascent as to leave enough time to reach theboat or the shore.

Count your fin strokes.As if you were counting your steps while walking, acomplete fin stroke is approximately 70cm, youcould try counting 30 fin strokes and then turningback. This method can be used to calculate distan-ces.

Naturally you shouldstart counting from aselected referencepoint, such as the refe-rence line or a rock.This method will be use-ful when you are notfamiliar with the divingsite. Many trips in diffe-rent directions are theeasiest way to exploreyour surroundingswithout getting lost.Practice counting yourfin strokes also using acompass.

Monitor the time.You should alwaysmonitor the time spentunderwater, once youhave decided the routeyou want to take, startswimming in one direction counting you fin strokesfor about 10-15 minutes, turn around and return toyour starting point using this method, checking thedepth and using the natural references.

Monitor your air supply. This is the most common method used by most diveleaders. Together with the fin stroke method, youshould also frequently monitor your pressure gaugeto make sure that you have enough air for yourascent, so as to calculate how long you can stay

2

Countthe fin

strokes isuseful toeasily estimate the distances

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underwater. Decide a direction to follow with yourcompass, swim in the direction and turn and goback once you have consumed 30-40 bar. By coun-ting the bar consumed and by keeping a constantdepth you will be able to dive without encounteringproblems.

Using the CompassYou have probably already had a chance to use thisinstrument during your Open Water Diver course. Ifyou haven’t yet had a chance to use the compassdon’t worry as the instructor will provide you witha compass for this dive and will explain how it

should beused.

The characteristics.The compass needle (usually in the shape of anarrow) will always point to the north. Holding thecompass in your hand you will see: North – N thatcorresponds to 0 or 360º, East – E corresponds to90º, South – S corresponds to 180º and West – Wcorresponds to 270º.

The lubber line, situated in the middle of the qua-drant, (it must be aligned with the diver body) isused to set a heading course and the swing lintelaround the compass, compass housing is used tohold the course.

Minitest1. Usually what you willsee out of the water will:a. Be different underwaterb. Have a consequenceunderwaterc. Continue underwater

2. True or False.It is not advisable to divefrom a sandy shore, asthere are no references

3. Whatever the kind oftypology a diver shouldstart observing referencemarks:a. Once he has descen-dedb. Already on the surfa-cec. Once he is holding onto the anchor line

4. A wall itinerary canstart towards ……….while a shole itinerarymight ………..:a. Left or right – followits outlineb. Right or left – followits boundaryc. a and b are both cor-rect

Answers: 1c – 2 False – 3b – 4c

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Instrument navigationIt is important to hold the compass in the correctposition to ensure that the needle doesn’t get stuck.In order to hold the compass properly underwater itis necessary to have horizontal buoyancy, take alook at the photos in this manual.

Underwater itineraries, with the aid of the com-pass you can plan underwater itineraries. Togetherwith your dive partner you will learn to plan astraight route itinerary, a back and forth itine-rary and a rectangular perimeter itinerary, theinstructor will check that you are carrying out theseexercises correctly. The first exercise will be a backand forth straight pattern. Keep still and align yourbody in the desired direction. Once you have deci-ded the direction to take, keep the compass in ahorizontal position, the needle will turn until thearrow is pointing towards the north. Turn the swinglintel keeping the needle in the set references, swimslowly following the route, calculate your fin stro-kes. To adjust a route, align your body with thelubber line and turn slowly until theneedle is between the referencesagain. Once you have completed theset fin strokes turn around until theneedle is pointing in the oppositedirection, a 180º turn, complete thesame number of fin strokes.

Rectangular patternFirst of all set your rectangular peri-meter using the four cardinal pointsand setting a fixed number of fin stro-kes. For each side of the rectangleyou could, for example, set 20 finstrokes for the long side and 5 fin stro-kes for the short ones and set one ofthe long sides towards the north.When the lubber line is pointingtowards the north start counting yourfist 20 fin strokes, stop, turn towards the east andcount 5 fin strokes, then again towards the southcount 20 and last towards the west count 5. Everytime you want to change direction towards yourright you need to add 90º or subtract 90º if you wantto go left.

Minitest1) Imparare a stimareuna distanza sott’acquaè utile pera. Pianificare il tempoper rimanere immersib. Pianificare la profon-dità alla quale immer-gersi c. Pianificare la lun-ghezza di un itinerariosubacqueo

2) I sistemi per calcolareuna distanza sott’acquacomprendonoa. Il conteggio delle pin-neggiate e il controllo deltempo b. Il controllo della pro-fondità e della visibilitàc. Entrambe le risposteprecedenti

3) Usando il metodo delconsumo dell’aria percalcolare un tragitto,devi controllare spessoanchea. La bussola b. La profondità c. La sospensione

2A dive teamnavigatingwith thecompass

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Underwater HazardsUnderwater you can use various methods for orien-teering. The sea is a liquid element that is alwaysmoving, this means that each dive may differ accor-ding to the conditions and the natural referenceswill appear to be different for each dive, no matterhow familiar you are with a particular site. (not consider the group of saupe feeding on the seaweeds)Sometimes you will have poor visibility and youwill find that the references you normally use areunreliable. Another factor to take into considerationis the current, as a matter of fact the current caninterfere with the compass and the pressure gauge,and it might make it difficult to count your fin stro-kes. You will find that when you are using theabove listed techniques, depending whether you aregoing with or against the flow of the current, yourdistance calculations will not be the same whenreturning to your starting point. This also appliesfor the air consumption, you will use more air whengoing against the current. Even a transverse currentmight push you off course. How can you preventthese factors from causing you problems? It is easy,first of all you should not rely only on one method,you should always combine the techniques andsecondly choose a reliable reference, as said before,you can use the anchor line.

Minitest1. To learn to estimatethe distances underwaterwill be useful to;a. Pre-plan the durationof the diveb. Pre-plan the depth ofthe divec. Pre-plan the length ofan underwater itinerary

2. The methods used tocalculate underwater dis-tances are:a. Counting the fin stro-kes, while checking thetimeb. Checking the depthand the visibilityc. A and b are both cor-rect3. Using the air con-sumption method fromcalculating the distancesyou should also use:a. The compassb. The depthc. The suspension

4. The magnetic needleof a compass alwayspoint towards:a. West b. South c. North

5. If you are following aroute and you need toturn a at a right angle toyour right, you should:a. Add 180°b. Subtract 45°c. Add 90°

Answers: 1c –2b –3c - 4c - 5c

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Open Water DiveOrienteering

BriefingPay attention to the description of each activityand ask questions when necessaryThe pre-diving briefing is very important as onceunderwater it is not possible to ascend every time ifyou are in need of clarifications. The instructor will explain what, when and how tocarry out the activities. Don’t hesitate to ask yourinstructor or dive leader any questions, they will behappy to help you.

Pre-planning, wearing and checking the equipmentPrepare, wearing and checking all the neces-sary equipment for the dive Prepare the Jacket and regulators, check your airsupply. The equipment wearing might vary depending onthe boat used to dive off, and it can be put on in orout of the water. The equipment check should be car-ried out carefully, any problem shouldbe reported to your instructor or diveleader.

Entering the waterEnter the water with the correcttechnique suited for the type ofdiveThe instructor or dive leader willinstruct you on the correct techniquefor entering the water according to thelogistics and the type of boat involved.

Controlled descent along a reference Descend using a reference line orthe natural references. Descendchecking your buoyancy, adjustyour descent speed with your jac-ket and stop in neutral buoyancybefore touching the bottomThe control of natural referencesduring the descent is a very importantphase of the dive.The descent line, a wall or a sloopingsea floor may be very important star-ting references.

Minitest1. To set the headingcourse you should:a. Keep the compass in ahorizontal position andalign your body with thelubber lineb. Keep the compass infront of your face andalign your body with thelubber linec. Keep the lubber linealways pointing towardsthe north

A dive team descending

Answer: 1 a

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Remember to descend in vertical stand-up position,this may be very usefull in order to control yourselfand to observe the surrounding natural references.You have also to signalling the choosed referencesto your Instructor.

Extimating the distanceExtimating the distance between two referencepoints by counting your fin strokes, two times(go and back)This tecnique is very usefull vhen you need to mea-sure a specific distance underwater. The Instructorwill give you all the necessary information about theselected reference points.

Using the compass for a straight line, back and forthrouteUsing the compass and counting a set numberof fin strokes cover a straight back and forthrouteYou should always use the compass together withanother orienteering technique, cover a straightback and forth route concentrating mainly on thefunctions of the compass. Pace yourself and moveslowly.

Using the compass to cover a rectangular perimeterrouteUsing the compass cover a rectangular pattern,selected by the InstructorThe instructor will choose the starting point for yourunderwater itinerary, you should only set a heading

route in the set direction and count thefin strokes covering the four sides ofthe perimeter and return to the startingpoint.

Use the Natural reference marksUsing only the natural referencemarks cover a straight back andforth routeThis will be the most used orientee-ring method during a dive. Duringyour descent try to memorise the loca-tion of the natural references, this willhelp you to find your way and to cal-culate the various distances

Controlled ascend along a referencean safety stop

A right angle turn with a compass

Minitest1. Underwater navigationproblems are usuallycaused by:a. Poor visibilityb. The currentsc. a and b are both cor-rect

2. A route can be chan-ged ………., especiallywhen ……………..:a. Transversally – there ispoor visibilityb. Transversally – there isa strong currentc. Accordingly – youneed to face the current

3. For orientation purpo-ses, underwater is it advi-sable to use:a. A compassb. Only the most impor-tant reference marksc. More that one orienta-tion technique

Answers: 1c –2b –3c

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Ascend slowly along the reference line (nofaster than 10 meters per minute) and carry outyour safety stop for 3 minutes at 5 metresIt is important to ascent slowly and to carry out thesafety stop. The body will have a chance to elimi-nate most of the nitrogen avoiding decompressionsickness. The instructor will show how the safetystop should be carried out.

ExitExit the water following the techniques sugge-sted by the instructor.

Taking off and checking the equipmentTake off your equipment and carry out thenecessary maintenance before storing it.During your pre-dive planning choose equipmentthat is appropriate and in good condition. Theequipment should always be rinsed in fresh waterbefore being stored away.

DebriefingPay attention and listen carefully to all theinstructions, recommendationsand suggestions during the debrie-fing, don’t hesitate to ask questionsand clarifications.

Dive validationInsert the details of your dive inyour logbook and have it signed bythe instructor.To validate your dives insert all thedetails in your logbook, such as con-ditions, temperature and personalcomments. Don’t forget to have itsigned by your instructor, and ask ifthere are any stamps or special stic-kers available to stick on your book.

2Pay attentionand listencarefully.The debriefingis one moreoportuniyto inproveyour divingabilities

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Congratulation!You have probably noticed that this unit coversmany topics that you have already learnt duringyour previous course, such as the natural referencemarks and how to use a compass. Underwater orien-teering and dive pre-planning are two extremelyimportant aspects when diving. If you follow all thesteps that you have learnt you will find that you willenjoy your underwater experience, and you will beon the good route to becoming a professional diver!

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What did youlearn?The purpose of this exercise is to go over what you havelearnt and to be sure to be ready to move on to the nextunit. Complete the multiple choice and hand it to yourinstructor, he will give you the necessary clarifications, ifneeded.

1) To find your bearing underwater you should:a. Locate the natural reference marksb. Improvise according to the environmental conditionsc. Calculate the distances and the consumptiond. Both a and c

2) For orienteering purposes when pre-planning yourdive you should consider:

a. What the bottom is made ofb. Using a suitable type of boatc. Diving with an expert diverd. Securing oneself to a rope

3) Near the shore, underwater, due to the _______ thesand/other forms _______:

a. Due to the backwash the sand forms waves perpendicular to the shore b. The waves form ripple marksc. The wave motion forms little parallel to shore waves d. Both b and c

4) When descending you should look towards the bot-tom, why:

a. Avoid feeling dizzyb. Calculate the depthc. Locate the natural reference marksd. Count the fin strokes

5) The boundaries of a reef are usually:a. Well marked if the reef is not too bigb. Undefined if the reef is not too bigc. Gradual and camouflagedd. Opposite and monochromatic

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6) The natural reference marks to be _______ shouldbe _______:

a. Memorised should be moving and colouredb. Memorised should be particular and stablec. Marked with coloured flagsd. Both a and b

7) The distances of an itinerary can be calculated by:a. Counting the fin strokesb. Calculating the time c. Calculating the air consumptiond. All answers a, b and c

8) The exercises to be carried out underwater are:a. Cover a straight line back and forth and a rectangular perimeter routeb. Cover a straight line back and forth and a triangular perimeter routec. Cover an articulated route with at least 5 direction changesd. Cover an articulated route with at least 7 direction changes

9) The compass will be in the correct position when_______, this will avoid the needle to_______:

a. Holding the compass in your hand will avoidthe needle to move freelyb. Placing the compass in your wrist will avoidthe needle to move freelyc. Holding the compass in a vertical position will avoid the needle to get stuckd. Holding the compass in an horizontal position will avoid the needle to get stuck

10) The current may represent a problem whendiving:

a. Going with the current means that on the way back the distance is greaterb. Going against the current means that on theway back the distance is shorter c. Going back with the current means that theoutward distance will be greater d. Both b and c

I declare that I have gone over all my answers with theinstructor and that I have understood all the clarifica-tions given to me.

Signature_______________________ Date___________

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Unit ThreeHover Dive

What will you learn?

Every time we walk, run, sit, our brain needs toelaborated information to be sent to our ner-vous system, we never give much thought of theamount of work it involves every time me move. Underwater it is extremely important to beaware of everything that concerns our move-ments. When we are underwater we need tomove in a certain way, for example when youare busy exploring a wall and havediscovered an interesting cave, doyou know what your feet aredoing? With a wrong movementyou might raise a sedimentcloud from the seabed andcause serious damage to theenvironment. With theexperience you will learnto control your move-ments and, therefore,your buoyancy. Intime you will moveyour legs with elegan-ce and you will alwaysknow what your feetare doing!

3

In this way itis easy tohold the belton the backuntill thebuckle isclose. Is better tokeep theweights atthe side toprevent backdisconfort

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Using your equipment correctly

Weight SystemDivers control their buoyancy by using a weightsystem and a BCB (Buoyancy Control Device). But how heavy should you be and where shouldyou position the weights?There are different options: the most common andcomfortable are the traditional weight belt and thepocket weight belt, it is easy to add and subtractweights, distribute the weight on your sides and infront near the buckle. This will help you to main-tain neutral buoyancy and the desiderable bodyposition.

Your back should befree of weights to avoidthe cylinder making apressure point.

Some BCDs are equip-ped with an integratedweight system. Your instructor will advi-se you and will help youto adjust your weightand will check that youhave neutral buoyancyonce you are in thewater. During the dive youwill be using up your airsupply making yourcylinder lighter and ligh-ter, it might be a goodidea, depending on thecylinder you are using toadd extra weight toavoid loosing you neu-tral buoyancy especiallyduring the safety stop.

If you find that your legs have positive buo-yancy you can use ankle weight,( 300 grams or 500grams each one). It is useful to lower the belt close to the hips. In thisway the legs will be more negative. The instructorwill guide you on how much weight to add.

BCDThe jacket or buoyancy control device (BCD) is a

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fundamental item when diving as it helps you tocontrol your buoyancy. It require you to make someexperience in order to obtain the best performances.The size of your jacket is very important, theygo from an extra-small to an extra-large make sureto choose one that fits properly, the Instructor, theDiveleader or the ESA Point personell will adviseyou and put you in the right direction. Just remember: the further you descend the heavieryou will feel, by inflating the BCD you will increasevolume and maintain neutral buoyancy, and vice-versa, as you ascent by deflating the BCD youcan continue to maintain neutral buoyancy. If the jacket is too big the water will cause a resi-stance slowing you down and if too small it willeven cause you not to breath properly. If you do not have your own jacket you mightwant to try a few out so that you can find a suitableone for your needs.

Make sure you place the jacket correctly on thecylinder or it might off set your buoyancy. According to the type of dive, you might want toplace the jacket higher or lower on thecylinder, there is not a fixed rule. To arrange and to tighten the BCDbuckle towards the high part of thecylinder allow one head positionoriented towards the high. If you arrange the BCD buckletowards the low part of the cylinder,you remain horizontal with the headtowards the bottom and the finstowards the high.You can choose one or the other posi-tion dependently by the dive type thatyou choose.

If you are using a dry suit you canadjust your buoyancy using the valve. You should always be wearing yourjacket during a dive, but you don’tneed to use it to adjust your buoyancyif you are already using the dry suitvalves. You can use your jacket tofloat on the surface. If you want to stay more warm andconfortable underwater you may deci-de to enroll in the ESA Dry Divercourse. A qualified ESA Instructor will

3The position ofthe BCD onthe cylindershouldinfluenceyour bodytrim

44

help you to learne the correct tecniques and thetheory information you may need.The hoses Maybe you will tried to run on the beach with thelegs into the water…you noticed the effort in orderto move yourself. Many persons use this system to train their legs or

for fun. Also while diving more resistancewe make greater will be the effort tomove.Just looking the shape of the fishesor marine mammals: they arestreamlines like a bullet or flat andlisciIt is better to reduce the equipmentresistance while diving.Think at the spare regulator hose:we could get it free in diving, buthow much water would it move?and as your dive partner could useit in case of emergency ?

The solution is easy. You must fixit with the appropriate accessorythat you will be able to hang tothe BCD.There are a lot of systems to holdthe spare regulator to the BCD butsomeone may be not suitable wenyou decide to change the mouthpiece of your regolator with a smal-ler one. Seek the help of your

Instructor or ESA Point staff in order to choose thebest type for your equipment configuration.Check the equipment before diving will help you tobe sure that your hoses are in the right position.Help your dive partner to check his equipment andlook the hose position: it has to remain under thearm.Also while diving use to check the right hosesposition.You can do it by tasting the hose holders on yourthorax.If you see the hoses of your partner not corectlyfixed advice him and help him to fix his hoses

Relax yourself befor diving:autogenous training

Specificaccessoriesare usefull tohold theregulatorrewady foruse

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There are not exercises to do in this phase, infact: tolearn the buoyancy control it is necessary to try itunderwater every time you dive and besides thisyou have to take care about the environmental con-ditions and your physical condition to enjoy whilediving.Is an usual think to your dive while assembling theequipment. There are particular emotions that just a diver canfeel.Mentally prepare yourself before each dive, a fewminutes are sufficient, close your eyes and con-centrate on your breathing. Breathe slowly and deeply, emptying yourlungs with long exhales. Now imagine to be hovering in the water exploringthe beautiful surroundings, imagine you are chasinga fish, you can see his coloured skin, the details ofhis body. Open your eyes, and still concentrating on yourbreathing look at the horizon. You are relaxed, con-tinue to breathe. This is only a brief example ofautogenous training. This type of exercise preparesyou for the wonderful experience you are about tohave.

Open Water Dive techniques Divers are usually people aware of the environmentand naturalistic activities, they like to hike, go onexcursions and birdwatching.To make the most of these activities one shouldfind his own rhythm: stopping to enjoy a sunsetor observing the flight of a bird or the movementsof small animals. Underwater the same rules apply. A beginner is eager to fulfil his sense of mystery andadventure, but also cannot wait to explore theunderwater world and to hover in mid water sur-rounded by a school of salemas, watching a barra-cuda swim past or observing the expanded polypsof a sea fan. All this is achievable once you havelearnt to control your buoyancy as it is important tomove without disturbing the environment, even acareless fin stroke could raise a sediment cloud fromthe bottom causing the equivalent of a tornadofor the immediate flora and fauna. You need to learn a few techniques that togetherwith the right gear and a relaxed mind will permityou to move correctly underwater, now just think ofall the things you can do underwater together with

Minitest1. When using a weightbelt, the weights shouldbe adjusted correctly to:a. Calculate the rightamount of weight nee-ded for the diveb. Distribute the weightequally when divingc. Leave the hands free

2. Using a mouthpiececlamp for your spareregulator is useful to:a. Avoid it from danglingcausing water resistanceb. To keep the spareregulator in an easilyaccessible positionc. a and b are both cor-rect

3. The spare regulatorhose should be positio-ned:a. On the rightb. On the leftc. Adherent to the bodyand ready to use

Answers: 1b – 2c- 3c

Mantainneutral buoyancyduring thedescent

NeutralBuoyancycheck onsurface

your ESA Instructor.

Checking the weight prior to dive During your Open Water Dive you have learnt howto check your weight before diving. This method

can be used both in the sea and infresh water. This exercise will be the first one inyour Open Water Dives. On the surface, wearing your equip-ment, put your regulator in yourmouth, deflate your BCD and breathnormally, the water should be atyour eye level. Adjust your weight by adding or elimi-nating weights. The BCD will helpyou to float, to start descending all youneed to do is deflate it and exhale.When floating on the surface the BCDwill help you to maintain your posi-tion without having to waste preciousenergy trying to keep afloat. The BCD will help when descendingwithout you having to use a referenceline to drag yourself down to the desi-

red depth.

Descending without refe-rences The first exercise will be to practicedescending without the referenceline, you will concentrate totally onyour buoyancy and equalisation. Why you may need to descendwithout a reference line?If you haven’t already been on adiving holiday in the Red Sea or atropical destination you will be ableto do so soon. In many of these tropical divinglocations boats are only permit-ted to anchor in certain places,this means that your guided divewill begin by jumping from a boatand descending without a referenceline, frequently with the bottom as

47

your only visual reference. You will learn to descend only with the aid of yourBCD, which you will need to deflate completely. To deflate your BCD you have to be in a verticalposition with your fins pointing towards the bot-tom while positioning the BCD control device in theuppward position and pushing the deflate bottom. Another method for deflating you BCD is usingthe quick release valve.You can activate this valve by pulling on a lineusually positioned near the shoulder. Some BCD also have a release quick release valvesthat is activated by pulling on a line positioned atthe back which can be used during uncontrolledascents. Occasionally, beginners can be seen floating on thesurface after having deflated their BCD, how canthis be possible? It is always a matter of concentration. Forexample if you are concentrating on your BCD youmight hold your breath making your descent moredifficult. Remember that your lungs are the bestinstruments for controlling your buoyancy, youneed to release part of the air in your lungs to beginyour descent. To do so all you need to do is exha-le slowly, start the descent once your instructor hassignalled to go ahead and once you have signalledto your dive partner. Deflate your BCD and breathedeeply into your regulator. This is the next exerci-se, upon your instructors’ request inflate your BCDuntil you can slow down and stop in mid water. Asyou know the pressure increases with the depth, 1bar every 10 meters. As you begin to descend theforce of the water above you will push you down-wards and the deeper you go the faster you will bepushed, it is important at this stage to slow downyour descent to equalise and to find your bearingsusing the natural references.

Buoyancy control during the diveAn author writing about the African landscapes said:“You need love, comprehension and humility tobreak the silence and the dignity of nature”. This may seem a phrase written to describedivers entering the underwater world. If you are diving in an area where there is a sandyfloor the rays of light filtering from the surface willfascinate you. If you stay completely still in proxi-mity of the sea floor you will be able to see thefunny hermit crabs carrying around their house or

Minitest1. Before the descent adiver should:a. Be used to strainsb. Learn a concentrationtechnique for relaxationpurposesc. Learn a few divingtchniques

2. A good concentrationtechnique could be:a. Breathing slowly anddeeply, imagining what itwould be like to be floa-ting mid-waterb. Think about your bestphysical conditionc. a and b are correct

Answers: 1b – 2c

Keep yourselfup to date:check yourhoveringevery timeyou dive

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the triangular rhombus swimming around like aspace ships. You can do it by resting moveless close to thebottom and without moving any particle ofsand.If the dive is along a wall you will assume a hori-

zontal or vertical posi-tion, sometimes you willbe head down exploringthe holes in the wall.You might be luckyenough to encounter alobster with his longantenna filtering foodthrough its mouth. Youcan swim about in midwater, swimming alongside with the marinewildlife and hope forturtle or a dolphin toswim by. Where shallwe begin?

HoveringWhichever dives youplan to do you have to

use specifically diving techniques.Before reaching the desired depth or the sea flooryour instructor will signal you to stop, try to restmotionless at that position without changing yourlevel. You should already have inflated your BCD duringthe descent and you should have neutral buoyancy.If on the contrary you want to assume a neutral buo-yancy position once you are on the bottom youshould inflate your BCD slowly to avoid ascendingtoo fast. Is not necessary use the arms to do it. Find a comfortable position and keep still, usuallydivers like the sitting position, with the legs stret-ched out or crossed. Breathing is the key, Thisexercise will make you understand how to use yourlungs correctly and will enable you to float in midwater without moving. You have learnt during theOpen Water Diver that inhaling makes you ascendand exhaling makes you sink, but you should neverhold your breath.

What needs to be done to keep still?Easy, the volume of your lungs should always beconstant, this can be done by breathing deeply but

49

not too slowly. You can check your position againstthe bottom and the surface. If you cannot maintainthe position don’t worry, try this exercise againtrying out alternative positions, for example: verti-cal with you fins towards the bottom or facingdownwards, watch your instructor he will demon-strate various hovering positions.Swimming strokesHave you ever tried the breaststroke underwater? This is a swimming technique but can be also usedwhen diving. Alternating various swimming techniquesunderwater will help you to rest your legs. Kick awide and slow fin stroke and then stop moving youwill continue to be propelled forward. If youuse this method you will notice that at the end ofthe dive you will have saved a lot of energy andreduced gas consumption.

Buoyancy and breathing If you are in proximity of the sea floor you will easilyfind obstacles in front of your path like a big rock ora tight passage, this means that you willneed to ascend or descend to avoidthese obstacles. It is a lot easier to control your buo-yancy with your breathing than byusing your BCD. Obviously the BCD is very important,but once you have reached the desireddepth and you are in neutral buoyancyyou can adjust your buoyancy withyour lungs. Try this easy exercise: in neutral buo-yancy swim horizontally, exhale toraise and inhale to sink. Practice thistechnique when hovering, in this caseyou can be in a vertical position, youwill find that by adjusting the amountof air in your lungs it will be easy toadjust your depth. Remember that at the end of the diveyou need to correctly deflate your BCDand be in neutral buoyancy.

Impact with the bottomNever touch the bottom is one of therules that divers should always follow,

3

Always reduce contact with the bottom alsowhen youwant closely obser-ve smallorganisms

50

as this may damage the environment. Sometimes itis inevitable to avoid contact, as you might need topush yourself away from a rock with a finger toavoid causing more damage by colliding with yourentire body. By pushing even with one finger in neutral buo-yancy keeping your fins completely still you will bepropelled backwards avoiding the collision. Try to limit any contact at all.When you are in proximity of the bottom youshould pay attention to your fin movements, the finstroke cause a water undertow and raise sandsuspension. Especially during a night dive you will not be verypopular with the divers behind you if you raise a bigcloud every time you move.Often divers complain that it is hard to maintain aposition as the fins have a tendency to floattowards the surface. This is not entirely a disad-vantage as in many situations the ideal position ishorizontal with the fins slightly upwards. Especially when wreck diving or during close rangeobservation you must have a complete mastery ofyour buoyancy

Ascending and carrying out the safetystop without a reference lineIf you haven’t used a reference line during yourdescent you will probably not use one during yourascent. Your ascent will be different according to the loca-tion and situation, for example: in the Red Sea theboat will be anchored to a buoy, while the Maldivesthe boat will not be anchored to a fixed buoy dueto the currents. Sometimes it is necessary to use the natural referen-ce marks during your ascent and it is not alwayspossible to have a support for your safety stop.Don’t worry, this will not be difficult, especiallyafter you have practised your hovering techniques.When your time is nearly finished start ascending ata speed of 10 meters per minute – you shouldalways check your speed and watch where youare going. If your descent was along a sloping shore just fol-low the same route during your ascent and if youdescended directly in deep water during your ascentyou should look towards the surface. Use your BCD gently and remaining in hovering, to

Minitest1. Once you have chec-ked weight to begin todescend you will need to:

a. Deflate the BCD and exhaleb. Deflate the BCD and inhalec. Deflate the BCD and shortly hold your

breath

2. To learn to descendwithout a reference markcan be useful:a. To prove you areexcellent diversb. When you will need todescent without a refe-rence linec. Because descent linewill only be an obstacle

3. When descendingwithout reference marksyou should:a. Deflate the BCD andequaliseb. Deflate the BCD, exha-le and equalisec. Deflate the BCD, equa-lise and slowing downyour descent

4. True or False.During the descent maybe necessary deflate orinflate your BCD.

Answers: 1a- 2b – 3c – 4True

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deflate your BCD put yourself in a vertical positionwith the head upwards, as you would do for anyother type of dive. Be extra careful during thelast 10 meters of your ascent where the pressuredecreases abruptly from 2 bar to 1 bar and the airwill expand rapidly in your lungs (remember theeffects of holding your breath underwater) and inyour BCD. Your instructor will guide you duringthis delicate phase of the dive.Safety stop without a supportOnce you have reached the last 5 meters of yourascent, the instructor will signal to stop and to carryout the safety stop. Check your position looking theinstrument and the position of your dive partner orthe surface. Don’t forget that your breathing willhelp you to maintain neutral buoyancy. Just before exiting the water make one last check,carry out your safety stop and resurface.

Checking your weight after the diveAt the end of the dive check your weight againstyour original weight, you will be able to verify thebuoyancy changes due to the consumption of the airsupply. It is not necessary to check your weight at thebeginning of each dive, but it is important to do soif you haven’t been diving for a while, if you arediving in fresh water or if you have changed yourequipment, in particular your wetsuit or your BCD.

Come all’inizio dell’immersione, ripeti l’eserciziodella pesata neutra. Questo ti sarà utile per verifica-re quanto lo svuotarsi della bombola abbia influitosulla pesata iniziale: l’acqua dovrebbe ancora arri-varti a livello degli occhi con il Gav sgonfio e tratte-nendo un normale respiro.Un ultimo consiglio. Ricorda che non è necessarioricontrollare la pesata ogni volta prima di scenderesott’acqua ma, sicuramente, è importante farlo dopoun periodo prolungato di inattività, quando t’im-mergi in acqua dolce o in un mare diverso e secambi attrezzatura: in modo particolare muta e Gav.

Minitest1. To stay in floating posi-tion when in mid wateryou should:a. Use your arms as paddles to prevent fromfalling backwardsb. Inflate your BCD withsmall amounts of air,breathing properlyc. a and b are correct

2. A fin stroke can be lessstressful if:a. Wide and slowb. Vigorousc. Using the crawl asswimming technique

3. True or False.When avoiding an obsta-cle underwater you willneed to use your BCD alot

4. You should ……….any contact with the bot-tom to avoid damagingthe environment:a. Absolutely avoidb. Respectc. Reduce to the mini-mum

Answers: 1b – 2 a – 3 False – 4c

A step of pre-diveactivities

52

Open Water DiveHoverBriefingPay attention to the description of each activityand ask questions when necessaryThe open water pre-diving briefing is very importantas once underwater it is not possible to ascendevery time clarifications are needed. The instructorwill explain what, when and how to carry out theactivities, so that you can enjoy your multilevel com-puter dive. Don’t hesitate to ask your instructor ordive leader any questions, they will be happy tohelp you.

Preparing your weight system, wearing and chec-king the equipmentCorrectly prepare your weight system and thenecessary equipment for the dive, wear andcheck it with the cooperation of your partner Before entering the water check your weight andyour weight system. You may start with your usualamount of load. Prepare the Jacket and regulators, check your airsupply. The equipment wearing may vary depending on theboat used for the dive, and it can be carry out in orout of the water. The equipment check should be carried out care-fully; any problem should be reported to yourInstructor or Diveleader.

Pre-dive Hover Training Concentrate on your relaxation techniques tobe carried out either on the boat or on theshore prior to divingRelaxing before a dive is important to make you feelcomfortable during your underwater activities.Dedicate a few minutes to concentrate will help youto feel yourself more comfortable while diving

Entering the waterEnter the water with the correct technique foreach diveThe instructor or dive leader will instruct you on thecorrect technique for entering the water accordingto the logistics and the type of boat involved.

Check your weight prior to diving

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Check if your weight system is efficient andthat you have the appropriate amount ofweight prior to descentChecking your weight is important for a correct buo-yancy. Put the regulator in your mouth, deflate yourBCD holding your breath for a short time. If thewater is at the eye level you have neutral buoyancy.A staff member will help you adjust your weightshould you be too positive or too negative.

Descent without referencesDescend checking your buoyancy, adjust yourdescent rate with your jacket and stop in neu-tral buoyancy before touching the bottomWhe the Instructor sign you, start to descend defla-ting your BCD and blowing out air from your lungs.Observe toward the bottom and note some visuareferences.Control your descent speed by slowly adding air inyour BCD, in order to reach the neutral buoyancy.

Underwater buoyancy control tecniquesKeep neutral buoyancy and try out the varioustechniques: hovering, swimmingstrokes, breathing, changing depthand limiting contact with the bot-tomThese “diving games” will help you togain experience in the underwaterworld. Try them out with your ESAInstructor.

Controlled ascent without referenceand safety stop Ascend slowly without referenceand carry out your safety stop for 3minutes while hovering at theselected deepEvery time you dive it is very impor-tant to ascent slowly (no faster than 10metres per minute) and to carry outthe safety stop. Try to carry out thistecniques without a reference, in orderto improve your buoyancy control abilities.

Check your weight at the end of the diveCheck your weight on the surface before get-ting out of the waterChecking your weight at the end of your dive, againto obtain neutral buoyancy the water should be at

3It is time to surface

54

the eye level. The instructor will help you to carryout this procedure.

ExitExit the water following the techniques sugge-sted by the instructor

Equipment desassemble and careRemove the equipment from the thank andcarry out the necessary maintenance beforestoring itThis phase is very important to mantain the scubaequipment efficiency. The equipment should alwaysbe rinsed in fresh water before being stored away.

DebriefingPay attention and listen carefully to all theinstructions, recommendations and sugge-stionsDon’t hesitate to ask questions and clarification.

Dive validationInsert the details of your dive in your logbookand have it signed by the instructorTo validate your dives insert all the details in yourlogbook, such as conditions, temperature and per-sonal comments. Don’t forget to have it signed byyour instructor, and ask if there are any stamps orspecial stickers available to stick on your book.

Congratulations!You should now be familiar with the buoyancy con-trol techniques. Now that you have tried out the wonderful sensationof floating in mid water you are ready for the ESAHover Diver or for other ESA speciality courses suchas photography or marine biology. Maybe you like the uw photography, the uw environ-mental knowledge. Could be the right way to carryout them with the diving activity.Ask your ESA Instructor or Diveleader for furtherinformation

Answers: 1b - False

Minitest1. When ascending thetwo main things toremember are:a. Ascend at your part-ners speed signalling“OK”b. Check your speed andwatch were you aregoingc. a and b are correct

2. True or False.The weight check shouldbe carried out beforeevery dive

55

What did youlearn?The purpose of this exercise is to go over what youhave learnt and to be sure to be ready to move on tothe next unit. Complete the multiple choice andhand it to your instructor, he will give you the neces-sary clarifications, if needed.

1) A diver uses the BCD and the weight system:a. for orienteering purposesb. to maintain a negative buoyancyc. only to control the descentd. to control the buoyancy

2) During a dive a diver will use his ______ in orderto ______

a. BCD – change the depth slightlyb. breathing – change the depth slightlyc. inhaling – change the depth slightlyd. exhaling – change the depth slightly

3) You should check your weight:a. on the surface deflating your BCD and holding your breathb. before every divec. when you change equipment or locationd. both a and c

4) To prevent water resistance a diver should wear:a. only light equipmentb. both c and dc. wear all the equipment close to your bodyd. hide the hoses under the BCD

5) Practising autogenous training prior to a divehelps to:

a. improve the divers physical conditionsb. improve the divers psychosomatic qualities c. relax and help to control the buoyancyd. relax and help to dive deeper

3

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6) To descend correctly it is important to:a. reach the bottom with negative buoyancy

and stand up on the bottomb. reach the bottom quickly and them inflate

the BCDc. equalise your descent by inflating your BCD little at a timed. equalise your descent by inflating all at once your BCD

7) To keep a neutral buoyancy while floating in midwater:

a. you should evenly distribute your equip-mentb. your weight should have been neutral

prior to divingc. you should Breath correctlyd. all of the answers

8) A diver should use a _______ fin stroke to:a. slow – to increase his diving timeb. moderate – save energyc. breast stroke– improve the timed. traditional - avoid cramps

9) True or False. During the ascent a diver shouldbe in positive buoyancy

10) Using a correct buoyancy helps the diver to:a. Reduce physical strainb. Reduce air consumptionc. Protect the environmentd. All the above answers

I declare that I have gone over all my answers withthe instructor and that I have understood all the cla-rifications given to me.

Signature_____________________ Date__________

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Unit FourDiving with the computerWhat will you learn?

Not so long ago people who worked inoffices or in the editorial business usedthe good old typewriter. A person whowas famous for being inseparable fromhis typewriter is Ernest Hemingway, allhe need to be able to work was his skillas a writer, some paper and his type-writer! I wonder what he would havethought about a modern lap top com-puter, the principles are the same: akeyboard and an electronic page forwriting. A computer provides you withmany functions, all you need is tolearn the basics and practice. Thecomputer gives you the opportunity toedit your text at any time you choose,making your work precise. Even in thescuba diving world computers have a fundamentalrole; the dive tables have been replaced with themore reliable and precise dive computer. The divecomputers are easier to use than the dive tables, asthese are limited and need to be used together with awatch and a depth gauge, it is also necessary to pre-pare all your calculations prior diving. In the firstparagraph of this unit we will cover the differences ofa square dive calculated with a dive table and amultilevel dive calculated with the dive computer.We will also cover the characteristics and generalrules to apply when using a dive computer. If youare considering buying a dive computer at the end ofthis unit you will find a few tips that will make yourlife easier!

4

Pre-diveplanning with the computers

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Square and multilevel diveDuring your Open Water Diver course, when youlearnt about dive tables you probably also heard ofa square dive. On the next page you will find a table that illu-strates how a square dive should be performed.Descend vertically to the desired depth, continue ona straight line keeping at the chosen depth andascend when you reach the no decompression divelimit, remembering to carry out your safety stop. Asquare or rectangle dive is calculated by the 2 hori-zontal sides given by the surface and the depth ofthe water and by the 2 vertical sides given by thedescent and the ascent time, you probably alreadyknow how to calculate a itinerary planning it follo-

wing the maximum depth of this kind. Before dive computer existed,divers calculated all the parameters ofa dive with the aid of the dive table(using the maximum depth reachedand the total dive time). For example, you want to dive andtake pictures of a wreck situated at adepth of 24 meters with a no decom-pression dive limit of 30 minutes. You descend vertically to the desireddepth of 24 meters, but you soon rea-lise that the best position for your pic-tures would be at a depth of 19meters: no worries, you are allowed toascend a little, the important rulebeing not to descend below the setdepth.

Already we have encountered our first problem: youhave reached the maximum depth allowed and youhave started to absorb nitrogen, and you cannotchange the pre-planned dive table calculationsfor safety reasons. The dive tables are an effective tool, but do not giveyou the possibility to calculate the nitrogen absorp-tion in real time. Dive computers calculate how much nitrogen isbeing absorbed depending on the depth you findyourself at the time – this type of dive is called amultilevel dive. Dive computers and dive tables both base their cal-culations on the same mathematical matrixes. The only difference is that a dive computer, thanksto a sensor that constantly monitors time and depth,will make on the spot calculations on how much

59

nitrogen is being absorbed depending on the depth. This will also avoid the inevitable dive table roundups. A dive computer will enable a diver to make themost of the time available. If you compare a square dive calculated with a divetable and a multilevel dive calculated with a divecomputer both pre-plan-ned at the same depth, youwill find that the secondoption will enable you tocalculate your depth meterby meter. This will give you moretime to spend underwater. In the next paragraph youwill find more informationconcerning the main cha-racteristics of these instru-ments.

Dive computers characteristics Modern dive computers are small instruments thancan be worn on the divers wrist or mounted on aconsole, activated by water contact. What you can see in the display. sDespitethe small dimensions these computers have a widedisplay and some models also come with a light tofacilitate reading when visibility is low. The display provides accurate information regardingdepth, maximum depth, and dive time. These com-puters might slightly differentiate depending on themodel. During the Computer Dive of the ESA AdvancedDiver Course you will spend some time spotting thedifferences between your computer and that ofyour partner’s and your Instructor.According to the depth where you are, the compu-ter will always give you the time you have left andyour no decompression limit, which will vary eachtime you change depth. Usually the computer starts to calculate the informa-tion once you have descended below a meter andcontinues to do so throughout the dive, until you

A computerwith a integratedpressuregauge

“SquareDive” scheme

surface

max depth

5 metressafety stop

get out of the water. Even if the four different areas for the data on thedisplay are the same in every computer, you canfind some difference about the display size andwhere the data are indicated.

When you buy a dive computer read carefullythe instructions, the dive leader and the instructorwill also show you how to monitor the informationEven when out of the water the computer will pro-vide information on how much nitrogen you stillneed to get rid off. When you buy a dive computerread carefully the instructions, the dive leader andthe instructor will also show you how to monitor theinformation.You can calculate eventual consecutive dive chec-king the resiual nitrogen time and the surface inter-val.You will also be able to monitor water temperatureand descent and ascent time. More sophisticated computers have also sound andvisual devices, sometimes you can set the Nitroxpercentage and read the amount of air andnitrox left in your cylinders, in this case a (fee-ler)sounding line will be connected directly withyour regulator. Computers also account for manmade error, forexample if you exceed the no decompression limitit will provide you with the information relevant tothe decompression stop. At the end of your dive thedive computer will also act as a logbook, keepingthe information stored in the memory. (like as bat-tery endurance,desaturation time) and you can inter-face it with the PC. In other words this instrumentis a real treasure, but as every machine it will not beable to replace man, so as usual you need to usecommon sense!

General rules to apply when using a computerPlanning an open water dive.As usual, when planning a dive, even if using a divecomputer, pre-planning is fundamental. The functions will change according to the modelyou are using, all you need to do is read the instruc-tions and ask the instructor to show you what youneed to do to calculate and access the information,it is not that different from using a dive table. In fact you will choose the maximum depth remai-ning well within the no decompression timelimits.

Minitest1. Diving computers cal-culate how much nitro-gen is being absorbed:

a. In a completely different way from the dive tablesb. With mathemati-

cal methods that differ completely from the

dive tablesc. With the same mathematical

models usedwith the dive tables

2. The advantage of amultilevel dive compa-red to a square one is:

a. Your dive will last longerb. Your dive not last

as longc. Dive time will be the same but you will

absorb morenitrogen

3. The dive computershave sensors that deter-mine the depth andtime, they can also:

a. Determine the amount of nitrogen absorbed and the dive time according to the depthb. Determine the amount of nitrogen absorbed for every 10 metersc. Determine the amount of nitrogen absorbed

Answers: 1c – 2 a – 3a –

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Remember that a computer will not be aware ofyour physical and emotional state.You should diving always with care.As we have already said dive computers constantlyupdate the information according to your presentdepth, even if you exceed the maximum depth allo-wed the computer will continue to provide you withall the information relevant to the new no decom-pression limit.(shorter than before) It is important torespect the limits and to keep to the pre-planningcalculations like you learnt from your Open WaterCourse.. The dive profile will be regulare starting at the maxi-mum depth and ascending slowly till the safety stop.

Now we will see what you can do underwaterwith a dive computer. Make sure while at the surface that the values are onzero, when you start descending observe the dis-play, the computer will start to elaborate the values. Reach the required depth and check the values withyour dive partner. Compare your values with your partner and theInstructor is an exercise foreseen during this course.

The important thing during any computer dive isnever to reach the no decompression dive limit, itwill not be difficult, monitor your display as youwould do with a pressure gauge. The no decompression limit will gradually decrease,make sure you start to ascend (for at least 5 meters)3 minutes before the time run out, and graduallymove to lower depths, this way your body willabsorb and release nitrogen in a safety way preven-ting the problems due to the sudden changes ofdepths. Together with your Instructor you will pre-plan adive (no deeper of 30 metres), including two diffe-rent depth levels, air supply permitting. If you were to plan a 30 meter square dive you willsee from your dive table that only 30 minutes wouldbe granted, while during your multilevel dive yourdiving time will probably be longer. During your Open Water Diver course you havelearnt that there is not a fixed rule for the onsetof the first decompression sickness symptoms. This can be caused by ascending to quickly or by notrespecting the limits, but can also be caused by aphysical problem or from exposure to the cold, somepeople can also be predisposed to this pathology.

Minitest1. On the dive computerdisplay you will find:a. Time, depth, maxi-mum depth allowed andtemperatureb. Time, depth, maxi-mum depth allowed andthe no fly timec. Time, depth, maxi-mum depth reachedduring the dive and nodecompression time

2. True or False.Before each multiple divea diver should wait thatthe dive computer signalsthe residual nitrogendesaturation time

3. Other important func-tions of a dive computerare:

a. Ascent speedb. Some dive computer models allow you to carry out a nitrox divec. a and b are correct

Answers: 1c – 2 False – 3c

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So there you go, as usual you need to use your com-mon sense and pre-plan carefully your dives.restricting your no decompression time limitalso with a dive computer.The physiological process while breathing compres-sed air are the same if you use dive tables or com-

puterBelow you will find afew recommendationsthat will help you whendiving with a computer:

• Each diver shouldhave a personal divecomputer - You mightuse a dive computervarious times during theday, so make sure to usethe same instrument foreach dive, purchaseyour personal dive com-puter as soon as possi-ble, it will become fami-liar as your regulator andyour mask.• Before diving, care-

fully read your dive computer instructions –Only this way you will learn the characteristics ofyour instrument and you will be able to plan yourdive and monitor the data relevant to your descentand ascent.• Before diving, pre-plan your dive carefullywith your computer and check your dataagainst the dive table – each dive computer has afunction to pre-plan and check your data beforediving. Plan your dive according to your experien-ce and keep well in the no decompression divelimit.• Compare your data with your partner’s dataand if there are discrepancies between the twocomputers use the more conservative values –There shouldn’t be enormous discrepancies bet-ween computers regarding the depth data, but somemodels could be more conservative than others.

Can a computer break?Of course, every mechanical and digital object canbreak. This is a rare event, but a dive computercould switch itself off, jam or flood, and for this rea-son it is important to make sure that your computer

Divers agree aboutthe changeof the depthlevel

Severalinstrumentson the bottom.Note the littlediffences on

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is in good working order before diving. Make sure that the battery is charged (read theinstructions for the modalities). If the computer functions regularly prior to thedive, it is unlikely that it will give you problems. Should a problem arise, such as the computer givesyou unreadable data, you should immediately abortthe dive, monitoring your partners computer for theascent information, you should not dive with onlyone computer!A good idea is to associate the use of the computerwith an digital integrated instrument. that willshows you at the same time depth, dive time, maxi-mum depth and water temperature.

Maintenance Your dive computer will not require a lot of mainte-nance, just make sure to remove the salt water rin-sing with fresh water and check the batteries regu-larly. Sometimes a qualified assistance is necessary tochange the batteries. Read carefully the instructions

When buying a dive computer

Reliability and functionsThere are many dive computer models on the mar-ket, each diving equipment catalogue has a selec-tion of dive computers. How to pick the right dive computer? A good bet is to buy a popular model: the most soldmodel and the most tested! Usually the latest models have more options andfunctions, but a dive computer should be chosenfor their mathematical model and their reliabi-lity. Only an intensive use can confirm the computerreliabilityWhen selecting your dive computer you shouldkeep in mind your physical conditions, your age

and the water tempe-rature. If for example,you plan to dive incold waters it might bewise to choose a moreconservative model.You can obtain all therelevant informationdirectly from themanufacturer or from

Minitest1. The most important thingto do when diving with adive computer is:

a. Check it once in a whileb. Check if it is switched onc. Never reach the no decompression time

2. It is important to be con-servative when diving, 3minutes before the nodecompression time youshould:

a. Ascent at least 5 metres and continue the dive at shallower deepthsb. Descent and remain at that level or deeperc. Wait until the no decompression time will be on zero

3. True or False.When scuba diving, physio-logical process will be thesame whether you are usinga dive computer or a divetable.

4. When buying a dive com-puter you should keep intoconsideration the:

a. Type of dive you need the computer forb. Auto reset capabilities of the computerc. The model and the colour of the computer

Answers: 1c – 2 a – 3 True – 4 a

Frequentlycheck divetime anddepth

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the catalogues, ask your dive leader or your instruc-tor for advice.

Open Water DiveComputer

BriefingPay attention to the description of each activityand ask for questions when necessaryThe open water pre-diving briefing is very importantas once underwater it is not possible to ascendevery time you need clarifications. The instructorwill explain what, when and how to carry out theactivities, so that you can enjoy your multilevel com-puter dive. Don’t hesitate to ask your instructor ordive leader any questions, they will be happy tohelp you.

Equipment preparation, wearing and checkingPrepare, wear and check all the necessaryequipment for the divePrepare the Jacket and regulators, check your airsupply. The equipment wearing might vary depen-ding on the boat used for the dive, and it can be puton in or out of the water. The equipment checkshould be carried out carefully, any problem shouldbe reported to your instructor or dive leader.

Entering the waterEnter the water with the correct technique sui-table for the type of diveThe instructor or dive leader will instruct you on thecorrect technique for entering the water accordingto the logistics and the type of boat involved.

Controlled descent using a visual referenceDescend along a reference line or a wall chec-king your buoyancy, adjust your descent speedwith your jacket and stop in neutral buoyancybefore touching the bottom or reaching your 30meter limitThe descent is a very important phase of your dive,you should be able to stop when needed as it mightbe useful for your equalisation, for prevent andmonitoring nitrogen narcosis and for prevent envi-

always rinse equipmentamd instruments

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ronment damage. You will pre-plan the dive withyour Instructor, while descending monitor yourdepth gauge and signal when you reach the desireddepth.

Experience dive at the maximum selected depth Practice monitoring time left, depth and airsupply. Signal to your dive partner and to theInstructor and ascend, for at least 5 meters, 3minutes before the no decompression divelimit

Experience dive – Level IIPractice the Level II dive, monitoring time left,depth and air supply. Signal to your dive part-ner and to the instructor and ascend, for atleast 5 meters, 3 minutes before the no decom-pression dive limit

Experience dive – Level IIIPractice the Level III dive, monitoring time left,depth and air supply. Signal to your dive part-ner and to the instructor and ascend, for atleast 5 meters, 3 minutes before the no decom-pression dive limit

Controlled ascent (with a visual reference) andsafety stopAscend slowly along the reference line (nofaster than 10 meters per minute) and carry outyour safety stop for 3 minutesIt is important to ascend slowly and to carry out thesafety stop. The body will have a chance to elimi-nate most of the nitrogen avoiding decompressionsickness. The instructor will show you how thesafety stop should be carried out.

ExitExit the water following the techniques sugge-sted by the instructor

Equipment desassembling and careDesassemble your equipment and carry out thenecessary maintenance before storing itThis procedure is very usefull for mantain the equip-ment and the computer efficiency. The equipmentshould always be rinsed in fresh water before beingstored away.

Debriefing

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Pay attention and listen carefully to all theinstructions, recommendations and sugge-stions during the debriefing, don’t hesitate toask questions and clarification

Dive validationInsert the details of your dive on your logbookand have it signed by the instructorTo validate your dives insert all the details in yourlogbook, such as conditions, temperature and per-sonal comments. Don’t forget to have it signed byyour instructor, and ask if there are any stamps orspecial stickers available to stick on your book.

Congratulations!The advantages that a dive computer gives

you are remarkable: youhave a lot more freedom.

The possibility of calcu-lating the differentlevels of a multileveldive on the spot gives

the diver more freedom andmore time to spend underwater.This instrument, that made its

debut in the 80’s, has become thedivers inseparable companion. As

per every innovated technology it iswise to be aware of the risks of animproper use, for this reason a diverneeds to learn a few essential rules and

recommendations. The dive computershould not replace your dive partner, and adiver should not think that the computer wouldaccount for his physical conditions. In anycase, if you always pre-plan carefully yourdives and keep within the certification limitsthe dive computer will offer you a wide rangeof advantages. If you still do not own yourpersonal dive computer, this might be a goodtime to purchase a modern model for all yourfuture diving adventures!

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What did you learn? The purpose of this exercise is to go over what you have learntand to be sure to be ready to move on to the next unit.Complete the multiple choice and hand it to your instructor,he will give you the necessary clarifications, if needed.

1) During a multilevel dive you can calculate:a. only one depth levelb. only two depth levelsc. more than two depth levelsd. exceed the recreational depth limits

2) Together with the instructor, using your dive computer, you will pre-plan:a. at least two depth levelsb. at least three depth levelsc. a 30 meter depth dived. both b and c

3) True or False. Every dive computer model willindicate the maximum depth allowed

4) Dive computers not only provide multilevel date,they also:

a. calculate consecutive dives, keeping trackof the amount of nitrogen and surface timeb. calculates four consecutive dives without keeping track of the amount of nitrogenc. memorises an electronic log for a certain number of divesd. both a and c

5) The essential rules when using a dive computerare:

a. read the instructions b. each diver should have their own dive computerc. compare data with your dive partner, andshould there be discrepancies use the more conservative datad. all answers are correct

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6) True or False. During a dive a good computerwill never give you problems

7) If during a dive your computer starts playing up,you should:

a. continue the dive using your dive partners’ computerb. continue the dive using your dive tablec. abort the dive and carry out a safety stopat 5 metres for the maximum time allovable d. abort the dive

8) The maintenance of your dive computer includes:a. rinsing your computer with fresh water after each diveb. after each dive rinse your computer with fresh water and check and replace the batteriesc. learn to dismantle your dive computer in case of malfunctioningd. both a and c

9) True or False. The selection of a dive computeris not important, as the mathematical calculations ofevery dive computer are the same

10) If you plan to dive mainly in cold waters youshould select your dive computer according to:t

a. The price of the dive computerb. A more conservative dive computerc. A wrist dive computerd. A dive computer that can be mounted ona console

I declare that I have gone over all my answers withthe instructor and that I have understood all the cla-rifications given to me.

Signature____________________ Date__________

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Unit Five:Night DiveWhat will you learn?

During the night dive you willexperience new fantastic sensa-tions and new practical aspects.The surroundings will change dra-stically at night time, this will giveyou the possibility to try out newequipment that you will needduring this dive. For many rea-sons you will want to try diving bynight, we will cover a few in thisunit. In the recreational divingworld a night dive opens the doorsto a new level of diving, obviouslya night dive needs to be well plan-ned, this is fundamental for safetyand enjoyment. You will find outthat a night dive is even morepractical than diving during theday time, at dusk many sites aresuitable for diving as the environ-mental conditions change. Eventhe marine creatures change theirhabits and you will be able toobserve them in full activity. Awhole paragraph will be dedicatedto the equipment used during a night dive.You will find information about various typesof illumination systems. This unit will alsocover information about orienteering techni-ques, to reduce the risk of getting lost. Last butnot least we will see what kind of organisms orfish we might encounter during a night dive,the habits of these animals varies a great dealduring the night from those during the day.

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Why diving by night? “ Diving by night was the most relaxing experienceI have ever had” divers often make this remarksonce they resurface for the first time after a nightdive. Many are the reasons why a diver decides to trynight diving and places this type of dive high onthe preference list. One of the main reasons to dive by night is toobserve the marine nightlife. By night it is easier to see certain organisms thathide during the day, these are not big scary creatu-res but creatures that might be unnoticedduring the day. This is bizarre, but at night with a good illuminationsystem the visibility is far better than by daylightbecause the torch light show up all the real colours. During the day the light cannot penetrate the waterand because of the reflectivity everything seems tobe blue, in a monochromatic underwater world it iseasy not to be able to see small organisms thatblend in with the surroundings. Night dive from the shore entering the water from

the shore opens up one of the bestdiving experiences, it is amazing whata crowded beach by day can offer bynight. Only in a night dive you can disco-ver the aquatic life on the sand. Many people might think that thewater is very cold in the night, but thisis not true, water can retain heat,especially during the summer when itis very hot. Selecting the appropriate diving site isvery important when planning a nightdive, the nightlife will also changeaccording to the site. During the next paragraphs we willanalyze all the different uw environ-mental to discover the different formof life

Night dive planningEverything you do when planning a day dive youhave to do in a night dive planning.When planning a night dive you need to pay specialattention to the following recommendations:what are you doing when planning a dive?Collect all the necessary information that you will

A tropicalcrab thatleaves it“home” onlyduring thenight time

By night it iseasy to findbig parrotfishes sleeping onthe reef

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need for your dive, location, characteristics of thesite, anchoring permits, depth, visibility and localcurrents, etc. Do you think that these characteristics changewhen its dark?If you had to walk through a dark alley to reachyour house the conditions will change dependingwhether it is night or day! Naturally you are probably familiar with this routeand you will probably take the necessary precau-tions. During a night dive you must be familiar with thesite and you must adopt the necessary safety pre-cautions keeping into consideration that the condi-tions will change drastically by night

Dive site choiceFor Example if you decide to enter the water fromthe shore you might want to snorkel in the shallowwater by day to find a suitable place to enter andexit the water, you could observe the bottom andthe natural reference marks. Instead if you want to dive in a site that can only bereached by boat, again you could dive in the samespot during the day to familiarise yourself with thelocation. If possible it might be a good idea to join a guideddive, you will have a qualified guide and you willattend a briefing and follow a set itinerary. This is a good way to obtain information for futuredives. A real best mix is to make a guided night dive inwhich you can find the specifically night dive equip-mentPicking a time is also an important aspect of nightdiving. During a summer day you will probably need towait to dive after 9:30pm, but in autumn it will bealready dark at 6:00pm. Make sure to reach the diving site in the light,this will facilitate your pre-diving operations, alsoalways relax a little before a dive even watching abeautiful sun set. Check the tide chart if you are diving in an areawhere this occurs. Another important thing to remember is to have thenecessary assistance out of the water. During a day dive a surface marker buoy i and adive partner t is enough in a night dive it i betterthat somebody remain outside to get assistance in

Minitest1. Many are the reasonswhy a diver decides to trynight diving and placesthis type of dive high onthe preference list

a. The sense of dangerb. The possibility of diving in shallow water avoiding the risks of nitrogen absorptionc. By night it is easierto see certain organisms that hide during the day

2. The water can main-tain …….. which is especially appreciated by……………..:

a. Heat – nightb. Density – nightc. Colours – night

Answers: 1c – 2 a

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the entry and exit phases.Your equipment should always be in working orderand you should not test new equipment on anight dive, it is better to use equipment which hasalready been tested on previous dives. This ruleapplies also to the illumination system you will use.

EquipmentApart from all the equipment normally used for anyother dive, during a night dive, divers need to beequipped with an illumination system: a portablelight and a fixed reference light. A portable light is a diving torch or lantern, thedive leader will provide a main torch, a spare oneand a luminous signalling device. The main torch is bigger and more powerful thanthe spare one, the spare torch can be hooked to theBCD and used in emergency. The individual luminous signalling device is asmall chemical light (cyalume) or a light charged bya battery, that comes in various colours and is usedto signal the divers position at all times, he has to befixed to each diver.

A good system is to fix it to the cylinder valve, thehighest point easy to view. The advantage of using a recharge battery light isthat it will last longer and although the chemicallight is environmentally friendly it is always some-thing that needs to be thrown away. If you intend to buy a diving torch an ESA staff

Minitest1. When pre-planning anight dive you shouldgive special emphasis to:

a. The time of the diveb. The selection of thedive sitec. a and b are both correct

2. Prior to night divingyou should:

a. Make sure you have a boat waiting on the surfaceb. Explore the dive site prior to divingc. Have a clear map of the dive site

3. When night diving itis advisable to use……….. equipment toavoid stress and pro-blems caused By:

a. Tested – manufacturing faultb. Old – manufacturing faultc. New – already tested equipment

Answers: 1c – 2b – 3 a

Esposizionedi torcesubacqueein un negozio

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member can give you advice. The ergonomics of your diving torch is veryimportant as it determines the shape, the weight,the position of the switch button (you should beable to switch your torch on and off with one hand)and the way you hold the torch. Many divers preferrechargeable torches,which are more expensi-ve but are much morepractical. Remember, ifyou go in a foreigncountry it is always use-ful to have a universaltransformer, which canbe found in every air-port.The uw fixed referen-ce lights are verypowerful lights thatcan be seen from agreat distance. Theselights are usually fixed tothe anchor line facingdownward at 2 metersunder the surface. Theguide sometimes uses this light to make himself visi-ble to the entire group. You can use whatever kind of torch for the fixedreference lights outside (gas, neon,etc..).If you are entering the water from the shore, thereference lights can be positioned lined up on thebeach, this will facilitate your descent and ascent atthe surface when you are looking for the exit point.. Maintenance Before each dive you should spentsome time checking that the torches are in workingorder. Check if the have the batteries are chargedand they are hermetically closed. Some torchesneed to be opened completely to replace the bat-tery, while others have a simple o-ring rubber plugthat protects the connections. Before diving in thewater make sure that the torches are working orderhermetically closed. It is always better not to usediving torches out of the water as the heat of thebulbs could melt the plastic parts of the torch. Asper all the other diving equipment the torchesshould be rinsed with fresh water after each dive.The batteries should be completely discharged befo-re being recharged again, make sure you havedried the torch before you plug it in.

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Night diving techniquesOnce all is ready, switch on your torch and jump inthe water. You will hold your torch with one handkeeping it on at all times, while you are waiting foryour dive partner to join you in the water, keep yourtorch in the water and take care not to shine it

towards the eyes of other divers.Try to remember this rule even duringthe dive. Before descending makesure your instruments are workingcorrectly, your computer should beactivated, shine your light briefly onyour pressure gauge it will becomephosphorescent. During the dive stayclose to your dive partner, a stressfulsituation could become very seriousshould you get separated or lost.When you need to signal to yourdive partner you can shine yourtorch on your hand. You can movethe light beam from side to side toattract your dive partner’s attention ormake a circle to signal that everythingis ok.

Navigation and orienteeringDuring a night dive it is always better not to dive toodeep for safety and orienteering reasons. The fixedlights are your start and finish point, and your refe-rence. Counting your fin strokes, cover a few shortitineraries keeping the fixed reference lights alwaysin sight. The instructor will make you practice a fewback and forth routes, if you are using the compass,shine the light on it to make it phosphorescent.Don’t worry! If you still have to do the orienteeringdive, your instructor will explain you everythingabout the use of the compass before the night dive.

What will you see underwater?A sandy stretch is where you will discover andencounter the most surprising creatures that areusually unnoticed during the day. Keeping neutralbuoyancy and without moving the sand, shine yourlight and you will be surprised at the number oforganisms that you will see. You will see sole fish and rhombus moving swiftlyon the bottom, hermit crabs carrying theirhomes and the precious load of sea anemones,cuttlefish and squids will swim towards youattracted by the light, you will see silver flashes of

In the beachit is possibleto makeamazingnight dives

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moving anchovies, sardines or mackerels. Rocky bottom and Neptunegrass prairie will alsooffer amazing scenarious. You might discoverschool of shining fisches - the big picarel - motion-less near the bottom in order to avoid the big pre-datory. You might encounter a white spotted octo-

pus (Octopus macropus) hiding between two rocks.Even the encounters with moray and conger eels,hunting small crustaceans, are not rare. A sea ane-mone, Alicia mirabilis, common in theMediterranean, the Red Sea and the Caribbean, canbe observed by night in all of its splendour. If youare lucky enough to see one keep a safe distance

Answers: 1b – 2c – 3a

Minitest1. The Main torch isusually ……… than the……….:

a. Bigger and not as strong – spare

oneb. Bigger and more powerful – spare

onec. Smaller and more

powerful –spare one

2. A personal signallingdevice can be:

a. The main torchb. A fixed light on

the ground or onthe boat

c. A chemical light ora small bat-

tery charges light

3. The personal signal-ling device should beplaced on the diver so tobe seen:

a. For 360ºb. Only from the frontc. Only from behind

Alicia mirabilisby night

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not to be stung by the long tentacles. At the end of your diveMove toward the refernce lights fixed under theboot o near the exit point on the shore. Start ascen-ding with your dive partner, control your BCD andbe prepared to dump air to control the ascent rate.Get the reference line if it is possible or followingthe bottom profile checking your instruments.During your safety stop you can observe the biolu-minescence all around you, small micro-organismthat produces shinning lights. As soon as you areout of the water switch off your torch, do notput it down on the sand or a rock that might scratchthe glass. Now you have just to rinse your equipment… andthink about the next night dive. If this night dive hascaptured your interested you will be able join theESA Night Diver speciality course and learn newtechniques, don’t wait any longer ask your dive lea-der for further information.

The Aliciamirabilistrasmormitself in aoppositeway ofDr.Jeckill eMr.Hidedone. Infact, youcan apre-ciate thebeauty ofthis creatu-re only inthe nigth

Minitest1. An important rule toremember when using adive torch is:

a. Not to shine them in the other divers’ eyesb. Should not be kept switched on out of the waterc. a and b are both correct

2. For underwater com-munication during anight dive you should:

a. Use the manual signsb. Use the light for signallingc. a and b are both correct

3. To increase your orientation during a night dive you should:

a. Increase the depthb. Decrease the depthc. Decrease the dive time

Answers: 1c – 2 c - 3b

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Open Water DiveNight

BriefingPay attention to the description of each activityand ask questions when necessaryThe open water pre-diving briefing isvery important, especially before anight dive, as once underwater it is notpossible to ascend every time youneed clarifications. The instructor willexplain what, when and how to carryout the activities, so that you can enjoyyour multilevel computerized dive.Don’t hesitate to ask your instructor ordive leader any questions, they will behappy to help you.

Pre-planning, wearing and checkingthe equipmentPrepare all the necessary equip-ment for the dive Prepare the Jacket and regulators,check your air supply, check that thetorches are working and that the bat-teries are charged, hook the sparetorch to the BCD. The equipmentmight vary depending on the boatused for the dive, and it can be put onin or out of the water. The equipmentcheck should be carried out carefully,any problem should be reported toyour instructor or dive leader.

Entering the waterEnter the water with the correct technique sui-table for the type of diveThe instructor or dive leader will instruct you on thecorrect technique for entering the water accordingto the logistics and the type of boat involved.Remember to switch on your light once you are inthe water, do not switch off the torch until you getout of the water again.

Descend following the fixed reference light beamsDescend following the fixed reference lightbeams, checking your buoyancy, adjust yourdescent speed with your jacket and stop in neu-tral buoyancy before touching the bottom

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A campinglight maybe useful tomarke theexit pointom land

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The descent is a very important phase of your dive,you should be able to stop when needed as it mightbe useful for your equalisation should any nitrogennarcosis symptom arise. As the visibility is very limi-ted keep the light beams always in sight You willpre-plan the dive with your instructor. Whiledescending monitor your depth gauge and signalwhen you reach the desired depth. If you decide touse the manual signs remember to shine the light onyour hand and never towards another diver.

Familiarizing during a night diveFamiliarize with your surroundings, estimatingthe distance by carrying out short back andforth routes using the light references or thecompass too for orienteeringThe instructor will ask you to carry out this exerci-se: memorise the starting point, counting your finstrokes and using the compass for orienteering, per-form short back and forth routes. This simple exer-cise will help you to familiarise with your surroun-dings. Try to locate the boat or the starting orentrance point so that you will know where to go atthe end of the dive.

Controlled ascent along a reference and safety stopAscend slowly along the reference line (10meters per minute) and carry out your safetystop for 3 minutesIt is important to ascend slowly and to carry out thesafety stop. The body will have a chance to elimi-nate most of the nitrogen avoiding decompressionsickness. The instructor will demonstrate how thesafety stop should be carried out, following thefixed reference light beams will help you in this pro-cess.

ExitExit the water following the techniques sugge-sted by the instructor

Taking off and checking the equipmentTake off your equipment and carry out thenecessary maintenance before storing itDuring your pre-dive planning choose equipmentthat is appropriate and in good condition. Theequipment should always be rinsed in fresh waterbefore being stored away.

Debriefing

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Pay attention and listen carefully to all theinstructions, recommendations and sugge-stions during the debriefing, don’t hesitate toask questions and clarifications

Dive validationInsert the details of your dive on your logbookand have it signed by the instructorTo validate your dives insert all the details in yourlogbook, such as conditions, temperature and per-sonal comments. Don’t forget to have it signed byyour instructor, and ask if there are any stamps orspecial stickers available to stick on your book.

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Congratulations!A night dive is one of those experiences that changeyour life, you will probably remember your first nightdive for a very long time. A well planned dive willgive you great satisfaction. Probably in the begin-ning you felt a bit over loaded with equipment, butall the equipment, especially the illumination systemis very important. You might not have used theemergency torch, but this does not mean you will notneed it, so you should always have it with you on anight dive. The ESA Night Diver Speciality Course,that foresees 3 night dives, will provide all the extrainformation, the emergency procedures and newtechniques.

Only by nightit is possible toclosely observefisches thatduring theday are veryshy like thisDogsteeth is.

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What did you learn?The purpose of this exercise is to go over what you have learntand to be sure to be ready to move on to the next unit.Complete the multiple choice and hand it to your instructor,he will give you the necessary clarifications, if needed.

1) A night dive gives you the opportunity to:a. improve your orienteeringb. learn new aspects of the underwater worldc. both a. and c.

2) If you decide to enter the water from a beach:a. a day reconnaissance of the area is not usefulb. a day reconnaissance of the area is very usefulc. you will probably not see anything interestingd. you should not have a suitable support station at the surface

3) The right conditions for a night dive are:a. also when diving just after the sunsetb. only when diving 3 hours after sunsetc. only when diving after midnightd. diving in the middle of the night

4) If you are not familiar with the place where thenight dive is taking place, it is best to:

a. select any diving placeb. enter the water only from shorec. enter the water only from a boatd. join a guided night dive

5) True or False. During a night dive, an essentialitem of your equipment should be a torch and asignalling device

6) The best fixed reference lights used during a night dive are:

a. a couple of gas camping lights placed underthe boat or near the entrance pointb. a couple of diving torches placed under the

La polpessaè un tipicoanimalenotturnodel Mediter-raneo

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boat or near the entrance pointc. a couple of stroboscopic lights placed underthe boat or near the entrance point d. A couple of psychedelic lights placed underthe boat or near the entrance point

7) True or False. Diving torches have to be com-pletely opened to replace or recharge the battery,make sure that the torches are hermetically closedand that prior to this operation you have degreasedthe o-ring

8) To signal ok during a night dive you can_______, to attract your dive partners attention youcan _______.

a. make a big circle with the light from your torch toward the eye of the dive part-ner – quickly move the light from side toside

b. make a big circle with the light from your torch toward the dive partner butpointing the bottom or the surface – quickly movethe light from side to side

c. point the light from your torch on your hand signalling “OK” – quickly move the

light from side to sided. Both b. and c.

9) True or False. During a night dive it is always betternot to dive too deep for safety reasons, and also becauseyou can find more of marine life activity in shallow water.

10) Once you have resurfaced from a night dive youshould _______ and once out of the water you should________.

a. Signal your position to those on the boat or onthe shore – switch off your torch to avoid overheating.

b. Switch off your torch immediately – switch itback on and leave it to discharge completely

c. Switch off your torch immediately – open the torch immediately to avoid condensation d. Signal your position to those on the boat

or on the shore – Signal your position to thosestill underwater.

I declare that I have gone over all my answers withthe instructor and that I have understood all the cla-rifications given to me.

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Unit Six:Ecological Dive

What you will learn

You have probably noticed that underwater themarine life unfolds in a variety of shapes andcolours. What at first might have seemed like a life-less rock or vegetation can turn out to be an intere-sting organism or fish. There arethousands of differentorganisms and fishmaking it difficult toremember the namesof each one. Duringyour dives you will learn todistinguish some of these creatures,like the octopus for example. This funny soft bodiedsea creature, with a big round head and eight ten-tacles, changes colour and squirts out a cloud ofblack ink which hides them and allows them to esca-pe. When you first start diving you might not paymuch attention to the marine life all around you,you will probably be too busy concentrating on allthe technical things you need to remember. The inte-rest and the wish to deepen your knowledge aboutmarine life may come at a later date. Just think thatin 1800 60% of this planet hadn’t yet been explored,and now-a-days we are exploring space! The sea isstill a mystery and there are still many things thatman knows little about, but the sea offers a fascina-ting spectacle, just put on a mask and lookingunderwater a extraordinary world will open up befo-re you!

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The food chains

ProducersDuring your Open Water Diver Course you willremember learning about the way the water, due toits density, absorbs the sunlight. This depends onthe depth and the movement of the water, whichtransform the light. Already from very shallowwater the light starts to loose its colours: red, oran-ge, yellow and so on, the only colour that filtersthrough the water is the colour blue. This lighttransformation conditions the distribution ofthe marine organisms.With the light, through a process called photosyn-thesis, plants produce organic substances andtherefore are called producers. The plants thatlive underwater and that you will observe duringyour dives are divided into algae and phanerogams. Algae can be divided in two kinds: the algae thatlove the light and the algae that prefer the shade.The three types of algae that can be observed in ourwaters are the green and the brown algae, whichgenerally are the light lovers and the red algae that

prefer the shade. During your dives youwill learn to distinguishwhat type of algae youmight observe depen-ding on the differentenvironments, a flatslope will be more expo-sed to the sunlight,while a rocky wall willbe more shady and dark.The colour of an alga isa good give away oftheir type but it is notalways the case. Agreen coloured algacould be a brown algaand a white colouredalga could be a greenalga! Codium bursa is

easily mistaken for a sea sponge for its roundedshape. The first algae that you will start to areAcetabularia acetabulum, which are formed by onlyone cell. The peacock tail seaweed (Padina pavo-nia) is white and fan-shaped. There are thousandsof algae that live in the sea: these producers surviveand produce organic substances, all they need is

In the tropi-cal areasprimari pro-duction isbased on asimbiosisamongmadreporasand algae

the foodchain of thewhales isvery shorty

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light, water, minerals and carbon dioxide and theyare at the start of the food chain. Phanerogams are similar to the terrestrial plants,they have roots and leaves and produce flowers andfruits. An example of phanerogam is Posidoniaoceanica (Neptunegrass). Posidonia oceanica mea-dows can only be found in the Mediterranean,many other creatures find their nutrients from thesemeadows.

ConsumersConsumers are those organisms, animals that feedon the producers, adding another ring to the foodchain. Many fishes in the Mediterranean are vege-tarian. Keeping yourdistance and neutralbuoyancy, stop andobserve, you mightnotice schools of fishbusy eating the algae.These vegetarian fis-hes are called 1stlevel consumers.Other organisms thatbelongs to this cate-gory are the seaurchins. These spinyanimals move slowlyalong the rocky shoresfeeding on the algae,they are also found inbeds of sea grass fee-ding on the stem androots of the Posidoniaoceanica. Many of you might know that it is notpleasant to be stung by a sea urchin spine, so do nottouch them. Well, you have already learnt a lotabout 1st level consumers.Another example of this category is the krill, whichunfortunately cannot be seen when diving. Thesetiny crustaceans are extremely important in the foodchain as they represent the basic diet for some wha-les. In this case, whales represent the 2nd level ofthe food chain. The filter-feeding whales orbaleen whales strain several tons of krill within justa few minutes. 2nd level consumers eat 1st levelconsumers, everybody has heard the saying “ bigfish eat small fish”, and this is basically what hap-pens: 2nd level consumers, according to theirsize can be a predator and a prey. Most of the

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You canobserve largeschools ofdamsel fishalso near thecoral reef

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time all of these species live side by sideVertebrates and InvertebratesAs soon as you start your descent you will notice allaround you different types of fish busily going abouttheir every day life, but fish are not the only inhabi-tants of the sea. In fact, animals can be categorisedinto two groups: vertebrates and invertebrates. Vertebrates have a spinal cord or backbone, inverte-brates do not. The marine vertebrates include alltypes of fish, marine mammals such as dolphins,whales, sea lions, reptiles such as sea turtles andmany types of birds such as penguins, cormorants,seagulls and albatross, etc. Marine invertebratesinclude a huge variety of species, such as sea spon-ges, sea anemones and jellyfish. There are manymore invertebrates than vertebrates.

FishFor tradition and culture fish have always been asso-ciated to water and that is why instinctively wesearch for them the second we are underwater. Allfish are vertebrates, this means that they have a car-

tilage or bone skeleton. Cartilaginous fish include sharks,skates and rays. Stingrays are verycommon in the Mediterranean, theybury themselves in the sand or softsediment, if you happen to encoun-ter a stingray do not approach it asit will flee in a hurry. Bony fish include about 25.000 ofspecies. In the Mediterranean youcan find many of these speciesdepending on the location whereyou intend to dive. Along a rockyshore or above a posidonia meadowyou will find yourself in the middleof a cloud of tiny fishes, calledChromis chromis (also: demoisel-le or black damselfish). When thewater is very clear you sometimescan see them from the boat. Thejuveniles of this species are electricblue so during the summer monthsafter the eggs have hatched, you willbe able to observe a multitude ofcolours. Other species that inhabitthe rocky shores are wrasses whichare easily recognised for their bright

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colours. A peculiarity of the wrasses is that somespecies build a round nest made of algae, justlike a bird!

A small Grey wrasse defending its net

The rainbow wrasse are found in southernMediterranean, this species is very territorial, stayingin neutral buoyancy you can observe these fish cha-sing all the intruders away from their territory. An important fish family easily observed in theMediterranean are the Sparidae, which includes thegilthead breams (Sparus aurata), the breams(Diplodus sargus), and the saddled breams (Obladamelanura). The Sparidae family is distinct for theirrounded heads and the silver markings, which chan-ge according to the type of species. Well knowntropical fishes are the Butterfly fishes. It is notalways easy to distinguish, even the bigger sized tro-pical fish, you need a very good reference guide.There is also the problem that many species hideduring the day and like to come out mainly at night,like the moray and conger eels, during the dayyou might find one hiding in a cave; do not molestthese reptile-like fishes as they could easily bite you.These are formidable predators and can be seenhunting during one of your night dives.

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Minitest1. What is the factor thatdetermines the distribu-tions of marine orga-nisms underwater?

a. The lightb. The currentc. The depth

2. At the base of the mari-ne food chain we canfind:

a. Fishb. Mammalsc. Plants

3. Vegetarian animalsare:

a. Carnivores and 1st level consumersb. Herbivorous and 1st level consumersc. Carnivores and 2nd level consumers2° livello

Answers: 1a – 2c – 3b

Two malesof topical cuttlefishesfighting toconquer afemale

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InvertebratesWell known invertebrates like the octopus or thecuttlefish are famous for their ability to camouflage,they can change colour according to the colour oftheir surroundings. Often during a dive the dive lea-der will signal the presence of an octopus and you

will need to concentrateon the outline of itsbody and eyes to beable to spot him.Octopuses are beautifulanimals, if you encoun-ter one you will see himchange colour in a mat-ter of seconds withincredible special effects!Cuttlefish do not spend alot of time on the bottomlike octopuses, they pre-fer to swim about undu-lating or flapping theirfins, if you were to scareone it would use thetorpedo-like shapedbody to disappear lea-ving behind a big

cloud of black ink! In the tropical seas squids arequite big, sometimes you can observe their courts-hip rituals, one male will fight off other males toconquer a female. These animals have long tenta-cles and big eyes. They also have a strong beak, ifthey feel threatened they could bite, so should youencounter one do not harass it in any way. Anotherinvertebrate is the starfish, like the urchins theymove slowly along the walls feeding on other inver-tebrates. A species common in the Mediterranean isthe red starfish, if you shine your diving torch youwill see the beautiful colour of this animal.

How do invertebrates obtain their food?Some invertebrates have peculiar ways of obtainingtheir food that distinguish them from the others. The most important species that can be observedduring a dive are: 1) animals that capture and eatthe particles and plankton that drift on the current,2) animal that eat the organic particles that sinktoward them, 3) animals that hold food from thesediment they swallow and 4) animal that catchfood by filtering the water.

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1 - If you happen to see flower like creatures withlong tentacles or filaments you are most likely loo-king at a sedentary organism. These invertebrates,such as coral and gorgonians, are organisms thatalways stay in one place and feed by capturing thezooplankton that drifts in the oceans current. 2 – In the Mediterranean you might observed longblack “T” shaped tubes resting on the bottom orcoming out from under a rock, what you are seeingis the proboscis of an animal very common in theMediterranean, a species of worm, called Bonelliaviridis. This proboscis is used to draw in the parti-cles of organic residues that deposit on him. 3 – Animals feed by swallowing mud, they digestthe organic matter and expel the debris throughtheir anus which on a different side of the body. Themost common creature that can be seen slowlymoving along the rocks and bottom is the seacucumber. 4 – The sponges are the most characteristic animalsof this group. You might not know that until themiddle of the 700’ sea sponges were thought to beplants and not animals. Sponges like to live in oneplace and feed by filtering organic matter from thewater.

SymbiosisAnimals and plants are quite different, but in certaincases two species can interact in tight association,such association is called symbiosis. The mostextraordinary example of symbiosis are the coral

A clownfishamong thethe tenta-cles of a seaanemonesis one ofthe mostamazingspettacle in the sea

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Minitest1. Fish are vertebrates,they can have a:

a. Bone and scaly skeletonb. Cartilage and scaly skeletonc. Bone and cartilageskeleton

2. Wrasses are verycolourful fish, they:

a. Lay eggs in a nestb. Give birth in a nestc. Their fins resemble the wings of a bird

3. True or False.The moray eel and theconger eel are snakesand not fish

4. Octopuses, squids andcuttlefish are:

a. Invertebrate fishb. Vertebrate fishc. Invertebrate animals

Answers: 1c- 2 a – 3 False – 4c

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reef environments, where a number of verymicroscopic algae live deep inside the tissue ofthe corals, exchanging each other the substancesnecessary for the life.A common example of symbiosis is the coexistenceof the clownfish with an anemone. The clown-fish, immune to the poisonous tentacles of the ane-mone, cleans his host while it protects the clownfishfrom predators. This association can be observed inthe tropical waters, even in very shallow waters.Another example of symbiosis is the interaction bet-ween the hermit crab and the anemone. Thehermit crab lives in a dead mollusc shell, which hechanges to suit his size. Anemones live attached to

these shells, when the hermit crab changes shells heremoves the anemone and places it on the newshell. The hermit crab benefits from the anemonespoisonous tentacles for protection, while the ane-mone captures the food that the crab moves bymoving on the bottom. We have already spoken about parasitism, someti-mes during a dive you might observe a fish with tinycreatures attached to his body, especially near thetail area, these are parasites that feed on the bodytissues of the host fish. Parasites can be observedattached to the gorgonians or even on the blackcoral of the Mediterranean, these parasites willeventually cover and suffocate the hosting plants.

Minitest1. A plankton feeder ani-mal:

a. Moves on the bottom to capture his foodb. Swims in mid water to capture his foodc. Stay in one place and feeds by capturing the small particles of food that fall on his tentacles

2. A filtering animal thathas small pores to intakewater is a:

a. Sea spongeb. Codium bursac. Sea flowers

3. A well knows exampleof symbiosis is the onebetween:

a. The Hermit crab and the anemoneb. The clown fish andthe anemonec. a and b are correct

Answers: 1c – 2 a –3c

A typicalsymbiosisbetweensome speciesof clean fishes andthe big tropical fishes

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Open Water DiveEcodive

BriefingPay attention to the description of each activityand ask questions when necessaryThe open water pre-diving briefing is very impor-tant, especially before a night dive, as once under-water it is not possible to ascend every time yourneed clarifications. The instructor will explain what,when and how to carry out the activities, so that youcan enjoy your multilevel computerized dive. Don’thesitate to ask your instructor or dive leader anyquestions, they will behappy to help you.

Pre-planning, wearingand checking the equip-mentPrepare all the neces-sary equipment forthe dive. Wear all theequipment and chek itout with the dive part-nerThe equipment mightvary depending on theboat used for the dive,and it can be put on inor out of the water. Theequipment check shouldbe carried out carefully,any problem should bereported to your instructor or dive leader.

Entering the waterEnter the water with the correct technique sui-table for the type of diveThe instructor or dive leader will instruct you on thecorrect technique for entering the water accordingto the logistics and the type of boat involved.

Controlled descent along a referenceDescend using a reference line or the wall.Adjust your descent speed with the jacket andstop in neutral buoyancy before touching thebottom or reaching the planned depth.

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Observation and identification of the species During your dive try to identify some of thespecies that you encounterYou will enjoy identifying the various species. Youdon’t need explore a vast area, just move slowly anduse the information received during your pre-divebriefing. A magnifying glass will help you to iden-tify the smaller organisms and concentration ofdetails such as the octopus camouflage, the pores ofthe sea sponges or the structure of the gorgoniasand the corral.

Controlled ascent along a reference and safety stopAscend slowly along the reference line (no

faster than 10 metersper minute) and carryout the 3 minutessafety stop metres at 5metresIf is important to ascendslowly and to carry outthe safety stop. Thebody will have a chanceto eliminate most of thenitrogen avoidingdecompression sickness.The instructor willexplain you how thesafety stop should becarried out.

ExitExit the water follo-wing the techniques

suggested by the instructor

Taking off and checking the equipmentTake off your equipment and carry out thenecessary maintenance before storing itThe equipment should always be appropriate and ingood condition. for this reason it should always berinsed in fresh water before being stored away.

DebriefingPay attention and listen carefully to all theinstructions, recommendations and sugge-stions during the debriefing, don’t hesitate toask questions and clarifications

Dive validation

A Little cuttle met during anight diveconfirmthat also thesmall organismsoften arevery interesting

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Insert the details of your dive in your logbookand have it signed by the instructorTo validate your dives insert all the details in yourlogbook, such as climatic conditions, temperatureand personal comments. Don’t forget to have itsigned by your instructor, and ask if there are anystamps or special stickers available to stick on yourbook.

Congratulation!In this unit you have found out a lot about the mari-ne organisms, which you can observe even in shal-low water. This is an advantage, as you will have

more time to spend under-water. The difference

between marine andland animals is con-

siderable, but youhave probablynoticed that theyboth need waterand light for their

survival. Youmight want to

l e a r n

m o r ea b o u t

all theaspects of

the marine lifeand what better opportu-

nity to deepen your knowledge with the ESA Eco divercourse, you will be fascinated with the mystery of theunderwater world.

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What did you learn?The purpose of this exercise is to go over what you have learntand to be sure to be ready to move on to the next unit.Complete the multiple choice and hand it to your instructor,he will give you the necessary clarifications, if needed.

1) The light is one of the main factors of photosyn-thesis: who benefits by this process is:

a. a plantb. a producerc. an animald. both a. and b.

2) The marine plants are divided in:a. trees and flowersb. algae and phanerogamsc. leaf and stalk plantsd. root and flower plants

3) An example of 1st Category consumer is:a. predatorb. preyc. herbivorousd. carnivore

4) True or false. A 2nd category consumers can beboth predators and prey

5) The sparidae is an important fish family it inclu-des:

a. Breams b. Tuna fishc. Dolphinsd. Moray eels

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6) An octopus lives ……………. while a cuttlefishlives……………:

a. on the ocean/bottom – in a hole on the ocean/bottomb. on the ocean/bottom – spends not so

much time on the ocean/bottomc. in mid water – spends lots of time on the

ocean/bottomd. in mid water – on the ocean/bottom

7) The most surprising characteristic of the octopus:a. is the big eyesb. is the long tentaclesc. is the big headd. is the ability to camouflage

8) During a dive if you happen to encounter anorganism similar to a flower with long tentacle likefilaments you are probably looking at a:

a) Debris feederb) Filter feederc) Plancton feeder plantd) Plancton feeder animal

9) The sea sponges are filtering organisms that:a. Sucks water and food through small poresb. Sucks water through a big mouthc. Capture their food with long tentaclesd. Capture their food with a trunk

10) The anemone benefits from his association withthe hermit crab because the hermit crab:

a. Stays in one place, the anemone finds it easier to capture his foodb. Moves along the bottom, the anemone

finds it easier to capture his food c. Stays under a rock, the anemone finds it easier to capture his foodd. Swims in mid water, the anemone finds it

easier to capture his food

I declare that I have gone over all my answers withthe instructor and that I have understood all the cla-rifications given to me.

Signature ______________________date__________6

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APPENDIX Dive planning outline General planningDive partnerDate and time of diveReason of the diveSelected dive locationAlternative dive locationRoute to reach the dive locationMeeting place and timeParticular equipmentWeather forecastAir supply checkEquipment checkTools and spare equipment checkWeight systemTransportationDive location informationEmergency contactsInformation for the contactsFood and drinksReservations/TicketsMoney

At the dive sitePhysical conditionsSea and weather conditionsCheck the communication systemDecide which techniques to use and where to enterthe waterDecide which techniques to use and where to exitthe waterDive partner systemUnderwater communication techniquesItineraryDepth and time limitsEmergency proceduresChecking the equipment

In case of an emergency, please contact ________

_____________________________________________

___________________________________________

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Not to be left at home

MiscellaneousID’sDive LicenceLog bookReservations/ticketsEmergency contactsSwim suitSun screenSun glassesHatWind breakerTowelBath robeSandalsGoggles and bathing capSpare clothingFood and drinksMedicines

EquipmentBagFins, mask and snorkelWet suitThermalsHoodGlovesBootiesWeightsBCDFull cylinderMain regulatorSpare regulatorPressure gaugeBCD pipeDry suit pipeKnife

InstrumentsDive computerDepth gaugeTimerCompassThermometerDive tables

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AccessoriesDive slateAnimal guidePencilDive buoySurface signalling deviceReelMain torchSpare torchStrobe lightPosition indicator lightSnap-hookAnti fog spray/liquidEquipment lanyard

Spare gearO-ringCylindersWeightsStrapsTool kitWet suit repair kit

Special equipmentUnderwater cameraLens and zoomsFlashFilmsVideo cameraHousingTapesVideo lightsBatteriesBattery chargerWiring and connector

Notes_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Suggestions to preservethe aquatic environmentIf you follow these simple rules you will give a greatcontribution to the preservation of the aquatic envi-ronment.

1) Control your buoyancy at all times. If you areneutrally buoyant you will avoid damages to the seafloor and its inhabitants. If you don’t wear glovesyou will be less inclined to touch and feel about thesea floor, causing possible damages.

2) When you approach the bottom don’t flap yourhands and fins around. If you have to rest on thebottom, make sure your knees and fins don’t causeany damage.

3) Avoid tunnels and caverns, by touching their cei-ling you could damage the life living on them, besi-des you bubbles could not escape and turn the topof a cave into a submerged desert.

4) Don’t hold on to sea turtles, large fishes and seamammals, just swim with them but don’t chase theanimals, they might not enjoy it as much as you.

5) Try not to touch animals you don’t know. Youmight get hurt or remove their protective mucusmaking them more vulnerable.

6) Do not remove anything from the bottom, shells(neither dead, nor alive), algae covered objects orarchaeological finds.

7) Do not buy souvenirs made with shells or othermaterials coming from the sea. It a way to discoura-ge their collection or fishing.

8) Do not litter the sea. Use the rubbish bins.

9) Carry on your training and extend your kno-wledge of the marine environment, you will disco-ver that every location deserves a dive and thatevery environment has amazing discoveries tounveil.

All the inhabitants and the visitors of the underwaterspaces thank you in advance for your effort

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Nine Safety Rules1 keep the equipment in good working order. Check it before to leave and before to make a dive.

2 Make sure you are in good physical condition.Working out and a good diet are important when diving. This willalso help you to prevent stress and anxiety, especially when youhaven’t been diving for a while. Start your dive relaxed, warm andhydrated.

3 Dive according to your experience. The conditions might be different to what you are used to. Deep diving, strong currents, cold water or poor visibility situations areall dive conditions that require specific training and experience.

4 Plan your dive and keep to the set plan.ITry to prevent any problems that might arise by being prepared,with your dive partner decide what parameters to use, time, signals,depth and limits.

5 Check your instruments and keep within thesafety limits.Even if you are familiar with your usual parameters doublecheck the data collected from the dive table and computer.

6 Relax during a dive, have fun, breathing conti-nuosly deeply and slowly.Breathlessness can compromise the breathing rhythm and the regu-lator functionality. If you feel tired stop and rest and if necessaryslowly ascend to the surface. When you are confortable underwa-ter look at what do you like to do underwater... ESA speciality cour-ses may offer you new opportunities and improve your techniques.

7 If you have any doubts abort the dive.IThis is the best way not avoid problems that you might not be able tosolve.

8 Ascend slowly and always carry out the 3 minutessafety stop at 5 meters before to surface .This is the best way to prevent Decompression Sickness.

9 Wait 24 hours before changing altitude like boardinga plane.after a dive it is always best to wait as long as possible beforechanging altitude.

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45 FAQ to refresh

divers mind

?

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1. The diving licence will be issued …………fromthe completion of the requirements:

a. 3 daysb. A weekc. By the instructor as soon as the course is completedd. None of the above

2. Keep the equipment in good condition and pre-vent any malfunctioning by:

a. After each dive rinse all the equipmentwith fresh water

b. Store all the equipment in a dry place andfar from heat sourcesc. Take apart all the pipes, the BCD valves and the regulatord. a and b are both correct

3. True or false. The regulator will supply air whenrequired and at the same pressure of the surronding.

4. When choosing a regulator it is important to takeinto consideration:

a. The priceb. The colour of the pipesc. That it can supply air even in difficult situationsd. The possibility to mount it both on the right and on the left

5. The purchase of personal equipment improves:a. Your comfortb. Your practicalityc. Your safetyd. All the above are correct

6. The BCD should be equipped with:a. Quick exhaust valveb. Descent buttonc. Pockets with zipsd. a and b are both correct

7. For a correct equalisation, a mask should:a. Be made of a very soft materialb. Should cover the nose of the diver and fitproperlyc. Should be equipped with two lensesd. Should have a strap made of soft neoprene

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8. At 10 meters of depth the pressure is at: a. 3 barb. 1 barc. 2 bar\d. 10 bar

9. During the ascent the volume of the gas contai-ned in a balloon:

a. Increasesb. Stays the samec. Decreasesd. Doubles

10. If during the descent equalising is difficult youshould:

a. Descend fasterb. Continue your descent forcing the equalisationc. Ascent a little and try descending by anticipating the equalisationd. Descend head first

11. The most important rule to remember whenscuba diving is:……………………….................……………………………………………………………….

12. If a cylinder last 30 minutes at a depth of 10meters, how long would it last on the surface:

a. 60 minutesb. 30 minutesc. 15 minutesd. 20 minutes

13. A floating object has a:a. Positive buoyancyb. Negative buoyancyc. Neutral buoyancyd. The buoyancy depends on the density of the liquid

14. A good buoyancy control is needed to:a. Limit the impact with the environmentb. Limit the energy consumption c. Prevent equipment damaged. All the above are correct

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15. The most important characteristic of the weightbelt is:

a. The possibility of putting it on quicklyb. The quick release bucklec. The material of what it’s made ofd. The size of the buckle

16. The bow of the boat is:a. The rear of the boatb. The front of the boatc. On the left sided. On the right side

17. To be able to use Nitrox you should:a. Learn the relevant theory knowledgeb. Satisfy the diving certification requirementsc. Obtain the diving licenced. All the above are correct

18. Why does sound travel faster underwater?a. Water is 800 times thicker than airb. Water is 80 times thicker than airc. Water is 8 times thicker than aird. Water stimulates hearing

19. To be able to see underwater:a. You need special lensesb. You don’t need special measuresc. You should have air between the water and the eyesd. All the above are correct

20. To prevent feeling out of breath you should:a. Swim slowly and stay calmb. Respect your pacec. Breath slowly and deeplyd. All the above are correct

21. If your air supply runs out and you are close toyour dive partner with a spare regulator, youshould:

a. Ascent immediately and exhaleb. Share your dive partners airc. Ascent together with your dive partner using the spare regulatord. B and c are both correct

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22. Usually any incident with a marine animal iscaused by:

a. The animals defensive behaviourb. The dive was not paying enough attentionc. The animals offensive behaviourd. A and b are both correct

23. To prevent problems caused by hypothermiayou should:

a. Drink lot of waterb. Stay in the shadec. Put on the wet suit just before entering thewaterd. All the above are correct

24. If you are in trouble during a dive you should:a. Ascent as fast as you canb. Inflate your BCDc. Stop and breath, everything will be okd. All the above are correct

25. The most important rule to remember whenscuba diving is:

a. Always apply the dive partner systemb. Try not to hyperventilate to much before divingc. Avoid strains during the dived. All the above are correct

26. For security reasons cylinders that ……………..cannot be refilled:

a. Have an expired check dateb. Are two years oldc. Have the shoulder painted with black andwhile segmentsd. All the above are correct

27. The DIN connection makes sure that the firststage regulator is:

a. Fixed on the cylinder valve with a bracketand screwsb. Connected to the cylinder without a gasketc. Screwed directly to the cylinder valved. Adjusted for pressure below 3 bar

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28. Air is composed mainly by:a. Oxygenb. Nitrogenc. Heliumd. Hydrogen

29. In case of suspected decompression sickness theaffected divers should:

a. Lay down and keep calm b. Breath pure oxygenc. Be controlled by a doctord. All the above are correct

30. If you suspect that your dive partner is affectedby nitrogen narcosis you should:

a. Make him ascent a littleb. Descend and make him stay on the bottomc. Make him breath through the emergency regulatord. Unbuckle the weight belt

31. If your cylinder has been refilled with contami-nated air, it is important to:

a. Not breath deeply during your diveb. Resurface with at least 80 bar in the cylinderc. Inform the person responsible for refillingthe cylindersd. All the above are correct

32. During a dive, to enhance the colours youshould use:

a. A mask with magenta coloured lensesb. A diving torchc. A magnifying glassd. A full face mask

33. During a dive the majority of dive computerswill show:

a. The depthb. The time already spent underwaterc. The time remaining to be spent underwater within the decompression time limitd. All the above are correct

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34. To take full advantage of the services offered bya diving centre, you should bring:

a. Your diving licenceb. Your dive log bookc. Your IDd. All the above are correct

35. When going on a diving holiday you shouldconsider:

a. To take out an insurance policyb. Take as much diving equipment as possiblec. Bring a authenticated copy of your documentsd. a and c are both correct

36. When travelling by plane you should:a. Not dive the last day of your holidayb. Leave your terrestrial excursions for the last few days of your holidayc. Follow the altitude rule after a dived. All the above are correct

37. For a fun and safe dive you should:a. Be in good physical conditionb. Eat sensibly without overdoing itc. Rest adequatelyd. All the above are correct

38. The major factor responsible for the movementof water is:

a. The windb. The wavesc. The currentd. The tides

39. Breakers and surges:a. Should be avoidedb. Can be tackled with special equipmentc. Can be dangerousd. a and c are both correct

40. If you encounter a surface current you should:a. Swim as fast as you can against the currentb. Descent and wait until your air supply runs outc. Keep positive buoyancy and ask for helpd. Keep a slightly negative buoyancy and swim vigorously

41. If it rains:a. It is forbidden to diveb. It is possible to dive only if the other weather conditions are good c. To dive you need a professional diving level licence d. You will consume more air than during anormal dive

42. True or false. Even when diving with a divercentre facility there are some aspects of dive pre-planning that must be considered.

43. Prior to any kind of activity, immediately beforediving you should:

a. Take into consideration the weather conditionsb. Assemble the equipmentc. Measure the water temperatured. Check your dive partners equipment

44. The surface time is:a. The time it takes to reach the diving siteb. A lunch breakc. The time between a free dive and anotherd. The time between two descents

45. The time limit for a 18 meter depth dive is:a. 55 minutesb. 60 minutesc. 50 minutesd. 52 minutes

Check your answers in the nextpage.If you have any dubt,please check it withyour ESA Instructor

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Correct answers

1c2 d3 True4 c5 d6 d7 b8 c9 a10 c11 Never hold your breath!12 a13 a14 d15 b16 a17 d18 a19 c20 d21 d22 d23 d24 c25 d26 a27 c28 b29 d30 a31 d32 b33d34 d35 d36 d37 d38 a39 d40 c41 b42 True43 a33 or more

correctanswer?Well done! You are an upto date diver!

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44 d45 c