PADI Open Water Diver Manual_03

During your first two confined water dives,you experienced the underwater environ-ment for the first time. Even then, you prob-ably noticed some underwater conditionsthat vary and affect divers.

If a relatively empty environment like aswimming pool or confined water site hasenvironmental variables, just imagine thevariables you can find at unconfined divesites depending on weather, climate and

THRE

E

The Dive Environment

The Dive Environment

Dive Planning

Boat Diving

Problem Management

Confined Water

Underline/highlight the answersto these questions as you read:

1. What six general environ-mental conditions can affectyou in any aquatic environ-ment?

2. How can you obtain an orientation to an unfamiliaraquatic environment?

MAINObjectives

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other factors. The conditions that mostdirectly affect you when you’re diving are:

1. Temperature2. Visibility3. Water movement4. Bottom composition5. Aquatic life6. Sunlight

Perhaps one of diving’s greatest appealscomes from the diversity of environmentsyou can explore. You can explore rivers,lakes, quarries, ponds, tropical seas or tem-perate oceans, each with its unique charac-teristics and its unique attraction. Weather,climate and season affect environmental

Dive Preview

General Open Water Skills

Open Water Dives 1 and 2

Chapter Three 123

conditions, so your dive experiencesat a specific site will vary depend-ing on the time of year.

During this section, you’ll get anidea of how environmental condi-tions can affect you as a diver, plusbasic information about both salt-water and freshwater diving envi-ronments. Your instructor will tellyou a bit about the conditions youcan expect at the dive site whereyou’ll be making your first openwater dives.

124 Open Water D

ffect you as anvironment apply):

n to local diveheck all that

Assessment 1

Local wisdom.Keep in mind that whethe first time, you wantfrom, or better yet, divexperienced local dive

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On this subject, keep in mind thatwhen you’re planning to dive in anarea for the first time, you want toget an

orientation to the local area from, orbetter yet dive under the supervisionof, an experienced local diver. ThePADI Discover Local Diving experi-ence is one way to do this. This pro-gram is a guided tour by a PADIInstructor, Assistant Instructor orDivemaster that introduces you to anew dive environment, what’s interest-ing about it, what to watch out for, andany unique dive skills or proceduresyou need to know. This is not only pru-dent for safety, but a local orientationis the best way to end up at the betterdive sites and making the best dives.

1. Conditions that can adiver in any aquatic einclude (check all thata. sunlightb. temperaturec. water movementd. bottom composition

2. To obtain an orientatioconditions, you can (c

QUICKQUIZ Self

n you’re planning to dive in an area for to get an orientation to the local areae under the supervision of, anr.

TemperatureThe discussion on exposure suits andheat loss in Section Two made itpretty clear that as a diver, you needto pay attention to water temperatureand proper insulation. The amount ofinsulation varies with the water tem-perature, and the water temperature

iver Manual

apply):a. check with a local PADI DiveCenter or Resort.b. take a Discover Local Diving ori-entation.c. talk to an experienced local diver.d. check the local newspaper.

How’d you do?1. a, b, c, d. 2. a, b, c.

varies with where you are, the season, and tosome extent with the weather. Water tempera-tures range from -2°C/28°F (yow!) in polarregions to more than 30°C/85°F (ahhhh!) in thetropics. Within a given region, water tempera-ture usually varies, but not usually by morethan 8°-11°C/15°-20°F throughout the year. Inmoderate climates, that’s more than enough tomake a dry suit preferable during cool seasons,and a wet suit more than adequate in the warm ones.

You may find thmoclines in botfresh and saltwater, and theyespecially abrupin freshwaterlakes, ponds anquarries duringthe warmer seasons. The thermcline rises andfalls with seasotemperature.


3. How can you expect temper-ature to change with depth?

4. What’s a thermocline?

5. How shouldin an area kthermocline

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Water temperature often changes with depth,usually getting colder as you descend. Water
tends to form distinct layers based on tempera-ture, with a boundary so abrupt that in calmwater you can swim in warm water and stick
your hand into distinctly colder water. This is called a thermo-cline. The temperature difference above and below the thermo-cline may be as great as 8°-11°C/15°-20°F. Sometimes you cansee distortion at the thermocline, somewhat like the shimmeringrising from a hotasphalt road,caused by the mix-ing of two temper-ature layers.

you plan to divenown to have a?

er-h

’ret

d

-o-

nal

Hot and cold.Water tends to form distinct layers based on temperature, with a boundary soabrupt that in calm water you can swim in warm water and stick your hand intodistinctly colder water. This is called a thermocline.

To stay comfortable and avoid excessive heat loss, baseyour exposure protection on the water temperature at

Chapter Three 125

You learned in Sectiocreate a serious healtcold water can also ccations. Believe it or polar water (it is onelar underwater envirfort — but, diving in requires special equiand experience. You mthe PADI Ice Diver cyou with supervised water diving.

VisibilityPass a diver headed theaded away, and inv“Hey, what’s the viz?”dive significantly, so know. During your ophow to keep from redmeasure it, and when

126 Open Water Diver Manual

Nice and warm.You can dive comfortably in even polar waters if you use anappropriate dry suit. But diving inextremely cold water or divingunder ice requires specialequipment and training.

1. As you descend, most commonlyyou can expect a temperaturechange to ________ water.a. warmer b. cooler

2. While descending, a thermocline isa. an abrupt change to a layer ofwarmer water.b. a gradual change to a layer ofwarmer water.c. a gradual change to a layer ofcolder water.d. an abrupt change to a layer ofcolder water.

3. If you know there’s a thermocline, indive planning you shoulda. make no changes.b. choose your exposure protectionbased on the temperature at depth.

How’d you do?1. b. 2. d. 3. b.

QUICKQUIZ Self Assessment 2

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your planned dive depth,which may be cooler thanthe surface temperature.
Since bottom temperaturesand thermoclines may behard to predict, ask yourPADI Resort, Instructor orDive Center for local infor-mation. If you find unex-pected cool water, you andyour buddy may want torevise your dive plan andstay in the shallower,warm water.
n Two that body heat loss canh risk (hypothermia). Very

ause some equipment compli-not, you can dive in even of the world’s most spectacu-onments) with adequate com-extremely cold or icy waterpment, plus special training

ay find special courses (likeourse) locally that can providetraining in cold

oward the water as you’reariably you get the question,Visibility influences your

it’s the first thing you want toen water dives, you’ll learnucing the visibility, how to it’s too poor to dive.

You define underwater visibility based on how faryou can see horizontally. Since this can be some-what subjective — sometimes you can see a silhou-ette but not much else — some divers add that thevisibility is the horizontal distance you can recog-nize another diver.

Visibility ranges from 0 to more than 60 metres/200 feet.

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Factors that affect visibility include 1) water movement, 2)weather, 3) suspended particles and 4) bottom composition.
Waves, surf and currents churn up sediment, and rainrunoff commonly clouds visibility. If disturbed by yourkicks, the boat wake or other water movement, fine bottomsediment can swirl into the water, quickly ruining visibility.In certain conditions, suspended microscopic animals(plankton) and plants (algae) proliferate and cloud thewater — oceanic plankton blooms called red tides can be soextreme that they kill fish and turn the water reddish.
Underline/highlight the answers tothese questions as you read:

6. What’s the definition of “under-water visibility”?

7. What four principle factorsaffect underwater visibility?

8. Restricted visibility can affect

MAINObjectives

The effects of some visibility conditions are obvi-ous, while others are more subtle. In limited visibil-ity, it’s more difficult to stay with your buddy and

to keep track of where you are and where you’re going. Youmay feel disoriented when you can’t see the surface or thebottom for reference.

To handle these concerns, stay closer to your buddy thanyou might usually, where you can watch each other. Trackyour position using your compass and noting conspicuousfeatures (you’ll learn more about using your compass inSection Five). You can remain oriented while ascending anddescending by using a reference line, or when shore diving,by following the bottom to and from deeper water.

If visibility is really poor, you may want to do somethingelse. But with special training and experience, you mayfind you enjoy the challenges of diving in extremely limitedvisibility — you may find it surprising, but many divers do.You can learn more about the skills and challenges of lowvisibility diving in the PADI Underwater Navigator andSearch and Recovery Diver courses.

you in what three ways?

9. How do you avoid the problemsassociated with diving in clearwater?

What you see, not how far.With special training and experience, youmay find you enjoy the challenges of divingin limited visibility — many divers do. Youcan learn more about the skills andchallenges of low visibility diving in thePADI Underwater Navigator and Search andRecovery Diver courses.

It may sound strange, but diving in extremely clearwater requires some caution. Because water magni-fies, the bottom may appear closer than it really is.

As you descend, you need to watch your depth gauge (orcomputer) and stay within your planned depth limit. Eventhough you can see the bottom and the surface, you canexperience disorientation (vertigo) during descents andascents without a reference in clear water. Again a line or

Chapter Three 127

Trying to swimagainst even a mildcurrent can quickly


Air clear.Diving in extremelyclear water mayrequire some caution.The bottom mayappear closer than itreally is and, you canexperiencedisorientation duringdescents and ascentswithout a reference.

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other reference helps avoid this problem.And in clear water, remember to stay closeto your buddy — just because you can seeeach other doesn’t mean you’re close enough.

CurrentsEarlier, you learned to remain relaxed, avoidover exertion and take it easy while diving.You also learned that water resists yourmovement, which is why you streamlineyourself as much as possible. So it followsthen, that when you have a current pushingagainst you, you need to learn some tech-niques to avoid getting breathless and tired,to avoid using your air too quickly, and toavoid long, difficult swims back to the boator shore. Let’s start by looking at whatcauses current.

1. You define underwater visibility as:a. more or less the great-est distance you can seein any direction.b. the least distance you can see in any direction.c. the approximate distance you can see horizontally.

2. Factors that affect under-water visibility include(check all that apply):a. water movement.

3. Restricted visibility cancause (check all thatapply):a. buddy separation.b. disorientation.c. loss of direction.

4. When diving in clearwater, it’s recommendedthat you:a. use a line or other ref-erence when ascendingand descending.b. close your eyes to avoidvertigo.


Currents are massmovements of waterand occur in oceans,but also in largelakes, seas and evensmaller water bod-ies to some extent.Some currents areglobal and relativelypermanent (moreabout these in abit), while othersare temporary andcaused by 1) windsblowing over thesurface and 2)unequal heatingand cooling of thewater 3) tides and4) waves.

b. suspended particles.c. bottom composition.d. fish population.

How’d you do?1. c. 2. a, b, c. 3. a, b, c. 4. a.

tire and exhaust you. It’s a lot of work, whichmeans you’ll burn through your air faster, too.This is why you need to use the right techniques,and avoid all but a mild current.

Underline/highlight the answers to thesequestions as you read:

10. What four primary causes generatesurface and underwater currents?

11. What should you do if you get caughtin a current and carried downstreampast a predetermined destination or

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When there’s a mild current at a divesite, begin your dive by slowly swimminginto the current so that at the end of the

dive, instead of fighting to get back to the boat orshore, the current assists your return. Avoid longsurface swims against even a mild current; you’llmake better progress on the bottom where thecurrent is generally weaker than at the surface.

exit point?

12. In most circumstances, which wayshould you go when there’s a mildcurrent present?

13. What should you do if you getexhausted and caught in a current atthe surface while diving from a boat?

If by accident you end up with a currentcarrying you past your exit point, don’ttry to swim against it. Instead, swim

across (perpendicular to) the current. Fighting a current by swimming directly into it willexhaust you. By swimming across the current,you may be able to swim out of the current,reach a line trailed from the boat, or reach theshore down current.

When diving from a boat, if you become caught in a current atthe surface and can’t get to the boat, don’t fight it. Fill your BCDto establish buoyancy (drop your weights if you have a BCD prob-lem), signal for help, rest and wait for the boat to pick you up.Above all, remain calm. Diving in strong currents and swift mov-

Chapter Three 129

Face the flow.When there’s a mildcurrent at a dive site,begin your dive by slowlyswimming into the currentso that at the end of thedive, the current assistsyour return to the boat orshore.

130 Open Water Diver

1. Causes of call that appla. wavesb. windc. tides

2. Under mostthere’s a cuyour divea. swimmingb. swimmingc. swimmingcurrent.

3. If a current planned exia. swim acroother exit pothe boat, orb. fight the c

4. When divingexhausted aat the surfaca. establish nal for help b. fight the ccan.

How’d you do?1. a, b, c. 2. b. 3

QUQUIZ

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ing water (like rivers) requires special trainingand experience, which you usually find in areaswhere you find those conditions frequently.

BottomCompositionYou spend most of yourtime diving near thebottom (’cause that’swhere all the stuff is).The bottom’s composi-tion can affect you andthe dive techniques you

something into a very svanish into the bottom.where you’re going, theentanglement in subme

Manual

urrents include (checky):

circumstances, ifrrent you should begin

with the current. against the current. perpendicular to the

carries you past yourt pointss the current to someint, a line trailed from

out of the current.urrent as best you can.

from a boat, if you getnd caught in a currente, you shouldpositive buoyancy, sig-and rest.urrent as long as you

. a. 4. a.

ICKSelf Assessment 4

Gear tight, fins up.Establish neutral buoyancy,keep all your equipment secure

want to use. You canloosely categorize com-positions as silt, mud, sand,rock, coral and vegetation.
All of these harbor aquaticlife and offer interestingdiving, with rock, coral andvegetation bottoms. Theseecosystems jump out at you,whereas it takes closerobservation to appreci-ate the fascinatingaspects of silt, mudand sand.
You can easily stir upsome bottom composi-tions, especially siltand mud, and somecompositions requirecare while entering andexiting, or while mov-ing about underwater.You may sink into asoft mud bottom whilewading, and if you drop

oft silt or sediment, it mayIf you don’t pay attention to

re’s some possibility ofrged trees, bushes, man-


14. Aquatic bottom composi-tions include what six types?

15. What are the two ways toavoid bottom contact?

MAINObjectives

and stay well off the bottom.Swim with your fins up to avoidstirring the sediment and reducing visibility.

made objects or aquatic plants. Rocks or coralcan cut and scrape if you’re careless. Obvi-ously, it’s important to know the bottom com-position and any problems associated with it.As you gain experience, you’ll learn to knowwhat type of bottom to expect in most cases,and how to cope with any associated prob-lems. It’s mainly a matter of awareness,watching where you put your feet and hands,and common sense.

Sometimes the bottom needs to watch out foryou. As you’ve already learned, some organ-

isms are so delicatethat even a lighttouch can damageor kill them. So ithelps you avoidproblems and mini-mize environmentaldamage to avoidcontact with anybottom that harborssensitive aquaticorganisms.

1. List the six general types of bottomcompositions:

1. ________________________

2. ________________________

3. ________________________

4. _________

5. _________

6. _________

2. To avoid bottoall that apply)a. pull yourselb. stand on yoc. remain neud. swim with ybottom.

How’d you do?1. silt, mud, sand,rock. 2. c, d.



16. What are the two basic classifi-cations for interaction betweendivers and aquatic life?

17. What causes nearly all injuriesfrom aquatic life?

18. What should you do if yousight an aggressive animalunderwater?

19. Nine simple precautions mini-mize the likelihood of beinginjured by an aquatic animal.What are they?

20. Why should divers follow localfish and game laws?

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Regardless of thebottom composition,effective buoyancycontrol provides the easiestway to avoid contact.Establish neutral buoy-ancy, keep all your equip-ment secure and stay welloff the bottom. Also, swimwith your fins up to avoidstirring the sediment andreducing visibility.Although you’ll learn torecognize insensitive bot-

tom that you can settle on without hurting the envi-ronment and without significant risk to you, it’s bestto avoid direct bottom contact as much as possible.

_______________

_______________

_______________

m contact, you (check:f along gently by hand.ur fin tips.trally buoyant.our feet up off the

coral, vegetation,

Chapter Three 131

Aquatic LifeInteraction with aquatic life. As a diver, you’ll interact with newand fascinating underwater organisms. Some will swim up to youcuriously, while others will flee in your presence. Some will freeze,solid as a rock. You may swim among aquatic plants that towerover you like a forest, or spread out beneath you like a manicuredlawn. This privilege carries with it a responsibility.


Leave nothing butbubbles . . .You can classify yourinteractions with aquatic lifeas passive or active.

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You can classify your interactionswith aquatic life as passive(watching, leaving undisturbed,photographing, etc.) or active(feeding, touching, disturbing,chasing, filleting, etc.) As thename implies, even passive inter-action affects aquatic life, whichis very sensitive to its environ-ment. Approaching aquatic ani-mals can cause them to altertheir behavior and the naturalrhythm of their lives. Move qui-

etly and smoothly — which is less likely to disturb them — andyou’ll have more chances to observe aquatic animals behaving nat-urally, rather than fleeing or hiding.

Active interaction means that you make physical contact withaquatic life. You already know that bumping into sensitive coral, forexample can harm it, and other active interactions like hunting,certainly don’t benefit the organism you affect. Other active inter-actions can appear to benefit the organism or environment, butmay or may not. Fish feeding, for example, can harm organisms ifyou feed them nonnatural foods; frequent, heavy feeding byhumans can alter normal behaviors and cause fish and other ani-mals to stop feeding on normal prey. This in turn creates a popula-tion imbalance that can widely affect the local ecology.

This isn’t to say there aren’t positive active interac-tions — freeing fish from an abandoned trap or sur-veying species populations to support protective reg-ulations, for example — but you need to take the responsibility ofensuring that your active interactions — intentional or accidental— cause minimal damage and disruption to the environment andorganisms you interact with. By doing this, you’re doing your part

http://www.projectaware.org/

to assure that your children, and theirs, will be able to see andinteract with the same creatures. You’re setting a positive exampleas the underwater world’s advocate and ambassador, and on abroader scale, you’re contributing to a healthier planet — somethingwe can all live with.

Aquatic animals. The typical aquatic animal respondsto human approach with “Run away! Run away!” Thevast majority are timid and harmless, yet fascinatingand enjoyable to watch. But there are a few that require your caution.

It is rare for humans to suffer attacks fromaquatic animals.

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Nearly all injuries involving aquatic life (plants or ani-mals) result from human carelessness, and the vastmajority are minor. It takes only a little bit of under-standing and care to avoid potential problems.

You’re far more likely to suffer from an unpleasant encounter withan unaggressive organism — such as a puncture wound from seaurchins, a sting from jellyfish and their relatives, or cuts andscrapes from barnacles and coral. To avoid these, watch what youtouch and wear an exposure suit as protection from accidental con-tact. If you’re not familiar with an organism, leave it alone. Anexcellent rule of thumb: If it’s very pretty, very ugly, or it doesn’t fleefrom you — don’t touch it! Venomous fish and other stinging aquaticanimals tend to have these characteristics.

Very few aquatic animals are outwardly aggressive. While it’s truethat almost any good sized animal is potentially dangerous whenprovoked, it’s actually very rare for humans to suffer attacks fromaquatic animals. The reputation of some animals as bloodthirstykillers, such as sharks and killer whales, resulted from inaccurateand distorted reports that became myths. The vast majority of inci-dents between sharks and divers involve spearfishing (wounded fishstimulate shark feeding behavior). Killer whales (more properly,orcas) have the capacity to harm humans, yet there’s no documentedcase of one ever attacking a diver.

Injuries from animals that may seem aggressive, such as eels andstingrays, actually result from frightening animals, causing them toreact defensively — such as if you carelessly stick your hand in aneel’s hole without looking first. (If a giant arm came in your frontdoor and started groping around your living room, you’d bite it, too.)

Chapter Three 133


Hands off.If you’re careful, you canavoid an unpleasantencounter with anunaggressive organism,such as a puncture woundfrom sea urchins, a stingfrom jellyfish and theirrelatives, or cuts andscrapes from barnacles andcoral. Attacks by aquaticanimals are very rare.

Sea urchin

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So if you see a shark, or some other potentially aggressiveanimal, remain still and calm on the bottom. Do not swimtoward it, which could trigger a defensive reaction. Watchit and see what it does. Chances are, it’s just passingthrough. And enjoy the experience — these are some of themost magnificent of nature’s creatures, and you don’t getto see them too often. If it stays in the area, calmly swimaway along the bottom, keeping an eye on it and exit the water.

These guidelines will help you avoid potentialproblems with aquatic animals:

1. Treat all animals with respect. Don’t tease or intention-ally disturb them.

2. Be cautious in extremely murky water where you mayhave trouble watching where you put your hands.

Potentially aggressive animals could mistake you for prey inmurky water, so you may want to avoid diving if they’re knownto be in the area.

3. Avoid wearing shiny, dangling jewelry. These can resemble baitfish or other small prey and can attract the interest of someanimals.

4. If you spearfish, remove speared fish from the water immediately.

5. Wear gloves and an exposure suit to avoid stings and cuts. Itgoes without saying that an exposure suit that covers yourwhole body offers more protection than cut off jeans and a t-shirt.

6. Maintain neutral buoyancy and stay off the bottom.7. Move slowly and carefully.8. Watch where you’re going and where you put your hands, feet

and knees.9. Avoid contact with unfamiliar animals. If you don’t know what

it is, don’t touch it.

While you may want to avoid contact with a few animals, thereare others that some divers seek as game or specimens. To name afew, these include lobster, crab, abalone, scallops, fish, clams, conchand other shellfish. Before collecting any game, learn local fish andgame laws, including seasons, size and catch limits and otherrestrictions. Fish and game laws exist to assure a continuing sup-ply of these animals for the future. If local laws permit game tak-

1. The two types of interyou can have with aqare (check two):a. passiveb. aggressivec. dominantd. active

2. Nearly all injuries fromlife result from:a. attacksb. diver carelessnessc. feeding behaviord. maternal protection

3. If you sight an aggresunderwater, you shouand leave the area cabottom if it remains oaggressive.True False

QUICKQUIZ

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ing, collect only what you can eat or use — even if the law allowsmore. Be reasonable in what you take, so that there can be game fordivers to enjoy in the future. Keep in mind that in many areas, thelocal dive community does not engage in game taking, even if legal.

Aquatic plants. The first thing you’ll notice is that it is far, far easierto sneak up on aquatic plants than many aquatic animals. Aquaticplants range from giant kelp forests common to New Zealand,California and other cool-water areas, to smaller grasses and algaein freshwater rivers and lakes. Plants provide food and shelter toaquatic animals, so you can usually expect lots of animal life inaquatic plant environments.

There’s a small possibility of entanglement in some plant types. Thisisn’t a serious problem, and you’ll find that with a little care, you canmove easily in and about aquatic plants without ever getting entan-

gled. Keeping yourequipment stream-lined, watchingwhere you go, andavoiding densegrowth areas helpminimize thechances of snaggingor tangling.

If it does happen,remain calm. Assoon as you feel thatyou’re snagged, stop,and back up slightly.Don’t turn around,which may wrapsome of it aroundyou. Chances are,you’re only hung byone or two strands,so reach back andfree yourself, withyour buddy’s help.Don’t struggle or tryto use force becausethat usually makes

Chapter Three 135

actionsuatic life

aquatic

sive animalld watch itlmly on the

r appears

4. Precautions you can take toavoid injury by an aquatic animalinclude (check all that apply):a. wearing an exposure suit andgloves.b. watching where you put yourhands, feet and knees.c. arming yourself with a spear-gun.d. not touching anything youdon’t recognize.

5. You should follow fish and gamelaws:a. to maximize the amount ofgame you take.b. to help assure future popula-tions of game animals.

How’d you do?1. a, d. 2. b. 3. True. 4. a, b, d. 5. b.

Self Assessment 6

things worse. Althoughyou want to minimizedamage to aquatic life,if necessary break freeby bending and snap-ping the stalk. This isusually more effectivethan using your knife.You’ll learn more abouthandling entanglementlater in this section.

SunlightDiving typically takesyou into direct sunlight aboard boats, on beachesand off of docks, so you need to take precautions toprevent sunburn. Out of the water, wear protectiveclothing (broad brimmed hats, light long sleeveshirts, etc.), stay in the shade as much as possible


Forest for the seas.Kelp forests create impressiveaquatic environments intemperate climates.

Underline/highlight the answerto this question as you read:

21. How can you prevent sun-burn while out of the water(three ways), and what twoways can you use to preventit while snorkeling?

MAINObjectives

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and use sunscreen. Keep in mind that a cloudy daydoesn’t protect you — the burning ultraviolet rayspenetrate the clouds, but since you don’t feel the

heat, you don’t realize you’re burning. That’s why you see some ofthe worst sunburns on overcast days.

You can also sunburn in the water, especially in shallow water while
snorkeling. Wear an exposure suit and waterproof sunscreen to pro-tect yourself while snorkel-ing, and remember that inwater you may not feel aburn until it’s too late.Sunburn is probably themost common “injury” diversexperience, and it’s entirelyavoidable. Don’t let sunburnruin a dive trip or vacation.
Fresh Water and Salt WaterAs you gain experience div-ing, you’ll probably discovergreat diving in fresh waterand salt water, even though

1. You don’t have to worry about sun-burn when it’s overcast, or whenyou’re in the water.True False

How’d you do?1. False. You can sunburn through

clouds and in water.


they differ in their conditions, animaland plant life, and call for different tech-niques and procedures. Dependingwhere you’re diving, you may pursueyour favorite underwater activity —photography, wreck diving, whatever —somewhat differently in freshwater than in salt water. Or you mayprefer entirely different activities in theenvironments.

Freshwater diving. Typical freshwaterdive environments includelakes, quarries, springs and rivers. Most of these offergood places for photography and exploration as well asmore adventurous activities like wreck diving, ice diving,cavern diving and swift-water diving. Some of theserequire special training and equipment before you partici-pate in them.


22. What are the general consid-erations for diving in fresh-water, and in saltwater?

MAINObjectives

Even far from the sea.Typical freshwater diveenvironments include lakes,quarries, springs and rivers.Most of these offer goodplaces for photography andexploration as well as moreadventurous activities likewreck diving, ice diving,cavern diving and swift-water diving.

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Freshwater environment dive considerations include cur-rents, bottom compositions, limited visibility, thermoclines,cold water, entanglement, deep water and boats — manyof the same considerations you have in salt water. Youmay dive in mountain areas well above sea level, whichrequires special techniques and training to account for

the altitude.

Since fresh water weighs less than salt water, you’re not as buoyantfor a given displacement. This means if you dive in fresh water afterdiving in salt water, assuming you’re wearing the same gear and ex-posure suit, you’ll need less weight. Keep in mind that you’re likelyto find a thermocline when diving in freshwater lakes and quarries.

Saltwater diving. The saltwater dive environment fits into threegeneral areas: 1) temperate, 2) tropical and 3) polar. The vast major-ity of recreational diving takes place in the temperate and tropicalareas, though as mentioned the Arctic and Antarctic offer spectacu-lar diving for those trained and equipped for it. Saltwater activitiesinclude all general diving activities, plus photography, spearfishing,and diving on artificial structures like jetties, piers, oil rigs, wrecks
and artificial reefs. General considerations for this environmentinclude waves, surf, tides, currents, coral, boats, deep water, marinelife and remote locations.
Chapter Three 137

Clearly, every place you dive has its own con-siderations, which is why you want to get alocal orientation to a new area. It makes yourdiving more fun, more enjoyable and safer.

Ocean DivingThe ocean is a dynamic environment that con-stantly changes and moves. It can be calm andtranquil, or angry and powerful. Its moodshave a direct influence on diving. So withoutassigning it any more emotions, let’s look atthe basic principles behind waves, surge, long-shore currents, rip currents, upwelling andtides. This way you’ll understand what you’llsee and experience ocean diving, and what youcan expect.

Waves and Surf. Most water motion that con-cerns you as a diver involves waves. The windforms waves by blowing over the ocean surface,with wave size determined by wind strength,and how long the wind pushes the wave. Astrong wind blowing continuously for severalhours can make waves large enough to trashthe conditions — making them either unfavor-able, or even hazardous. Once formed, wavescan travel across an entire ocean, affecting thediving hundreds of kilometres/miles fromwhere they formed.

A wave travels across the surface until windfrom another direction flattens it, until it grad-ually loses its energy, or until it encountersshallow water and breaks as surf. This phe-nomenon is the basis for an entire culture ofsurfboards and bleached hair.

Waves break in shallow water because thewave bottom drags on the sea floor; this slowsit compared to the wave top, causing the top ofthe wave to peak up and become unstable.Eventually the wave “stumbles” and breaks assurf, spilling its energy onto the beach.


Another world.The vast majority of recreational diving in saltwatertakes place in the temperate and tropical areas.

1. Freshwater dive considerationsinclude (check all that apply):a. deep waterb. altitudec. thermoclinesd. limited visibility

2. Saltwater dive considerations include(check all that apply):a. surfb. tidesc. marine lifed. waves

How’d you do?1. a, b, c, d. 2. a, b, c, d.


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Whether you dive in fresh or salt-water, you may encounter placesyou can swim into that don’t permit

you to swim straight up to the surface.Examples include inside shipwrecks, underice and in caves or caverns. These are calledoverhead environments. The may appeardeceptively safe and simple — but they’renot. They can pose hazards that you maynot recognize, nor realize are present untilit’s too late.

Your training in this course prepares youfor diving in open water — with directaccess to the surface at any time. As soon asyou lose the ability to ascend directly to thesurface, your risk and the potential hazardsgo up dramatically.

You can learn to dive in these environmentssafely — but it requires special trainingand special (often extensive) equipment tohandle the added risks and complications.For this reason, until you have the trainingand equipment you need do not enter a cav-ern, cave, wreck or any other overhead envi-ronment. Doing so places you in an unnec-essary and extremely hazardous situation.

Many overhead environments may seeminviting and safe, but any time you can’tswim directly up to the surface, you’re in aspecial situation. A sobering thought: One ofthe leading causes of diver fatalities is going

into overhead environments without theproper training and equipment. Those withproper training and equipment have anexcellent safety record in caves, wrecks,under ice and in other overhead environ-ments — those without this training(including otherwise highly trained diveprofessionals) have a very poor safety recordin these environments.

Avoid this risk entirely. Enjoy the fun andadventure of diving outside the overheadenvironment. If you’re interested in thistype of diving, get the training you need —but stay out until then.

Chapter Three 139

A deceptively easy way to die.Do not enter a cavern, cave, wreck or any other overheadenvironment unless you have the training and equipment youneed. Doing so places you in an unnecessary and extremelyhazardous situation.

Overhead EnvironmentsOverhead Environments

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The area where waves break is called the surfzone. Moderate to large surf can complicateentries and exits unless you use special tech-niques. You won’t find it difficult entering andexiting on a gently sloping beach through mildwaves no higher than, say, your waist (techni-cally surf, but not really considered “surf” inmost dive environments) — but you need spe-cific techniques to dive in higher surf.

Waves break in water only slightly deeper thantheir height, so watching the surf tells yousomething about the depth. An offshore reef,wreck or sand bar can create a shallow areathat causes waves to break. Offshore shallowareas can be popular dive sites, or hazards toavoid (something to learn during an area orien-tation). Sometimes you’ll see waves break,reform and break again. This indicates that thebottom rises, drops and then rises again as youmove seaward. Knowing what thewaves tell you helps you plan yourdive.

Sometimes waves approach shorefrom different directions. Dependingon the angles and timing, the wavescan combine into very large waves, orcancel each other out and diminishthe surf. This is why you often have aseries of smaller waves — or none —followed by a series of larger waves.When entering and exiting throughsurf, you watch the water and learnthe wave pattern, so that you cantime your entries and exits to passthrough the surf zone during the

small waves.

Avoid diving in large andrough surf. Not only can it be haz-ardous, but the dive conditions tend to


Underline/highlight theanswers to these questions asyou read:

23. What creates surge andhow do you avoid it?

24. What causes long shorecurrents, and how maythey affect you?

25. Why would a wave breakoffshore?

26. What causes a rip current,and how do you knowwhen there’s one present?

27. What should you do if youget caught in a rip cur-rent?

28. What causes an upwelling,and how might it affectlocal offshore dive condi-tions?

29. Tidal movement changeswhat three environmentalconditions?

30. What’s generally the besttidal level for diving?

MAINObjectives

Ocean in motion.Most water motion that concerns you as a diverinvolves waves. The wind forms waves byblowing over the ocean surface, with wave sizedetermined by wind strength, and how long thewind pushes the wave.

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be poor anyway. You need specialized surf trainingbefore attempting to dive in surf of any size. In surftraining, you learn to judge conditions and use thecorrect techniques for entering and exiting throughthe waves. Stay out of the surf until you have hadthis training. Keep in mind that surf diving tech-niques vary from area to area, and even from sea-son to season in the same area. Surf’s up.

Waves break in shallow water because thewave bottom drags on the sea floor; this slowsit compared to the wave top, causing the top ofthe wave to peak up and become unstable.Eventually the wave “stumbles” and breaks assurf, spilling its energy onto the beach.

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Surge. In shallow water waves passing overheadmove you back and forth. This is called surge. Surgecan move you an appreciable distance as largewaves pass over, and strong surge can be haz-ardous. It tends to dissipate as you go deeper, soyou can often avoid surge by planning a deeperdive. Avoid diving near shallow, rockyareas when there’s strong surge present.

Undertow. After a wave breaks, it flowsback into the ocean under oncomingwaves, causing undertow or backrush. Inconditions in which you’re likely to be div-ing, backrush usually dissipates at a depthno greater than about a metre/three feet.It’s not a current that pulls things far outto sea, but you do need to be aware of it. On sbeaches backrush can be quite strong; since thwaves push your upper body shoreward and tbackrush pulls your legs seaward, you have to payattention to keep your balance duringentries and exits. Avoid diving frombeaches with extremely steep shorelineswhen there’s anything more than verymild surf.

Currents. Waves cause many of the cur-rents that affect divers. They typicallyapproach shore at a slight angle, whichpushes water down the shoreline, creating

Flow underfoot.After a wave breaks, it flows back into theocean under oncoming waves, causingundertow or backrush.

a longshore current. A longshore currenttends to push you down the beach — awayfrom your intended exit area if you didn’t know toaccount for it. When diving in a longshore current,

teepe

he

Offshore clues.Waves break in water only slightly deeper thantheir height, so watching the surf tells yousomething about the depth. An offshore reef,wreck or sand bar can create a shallow area thatcauses waves to break.

Chapter Three 141

throughstrong,very quknow w

get cauface, inup and

Althougthe winlarge-scaffect dcurrent


Down shore, down current.Waves approaching shore at a slight angle push waterdown the shoreline, creating a longshore current.

Rushing water.A rip current occurs when waves push water over along obstruction such as a sand bar or reef. The watercan’t flow out on the bottom, so it funnels back to seathrough a narrow opening.

Rip Current

Beach

Bar

To Escape

Incoming Waves Incoming Waves

Rip Dispersal Area

Shallow Bar

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you can begin your dive up-current fromyour exit point, or dive into the current soyou can drift back to the exit at the end ofthe dive.

Another wave-generated current is the ripcurrent. A rip current occurs when wavespush water over a long obstruction such asa sand bar or reef. The water can’t flow outon the bottom, so it funnels back to sea a narrow opening. Because they tend to berip currents can carry you away from shoreickly, which can be alarming if you don’that’s happening and what to do about it.

You can usually recognize a rip current as a line ofturbid, foamy water moving away from shore; it

also disrupts the waves where it rushesseaward.

ghfla re

hd,alivs,

Obviously, you want to avoid rip currents.If you get caught in one, establish buoy-ancy and swim parallel to shore to clearthe rip area. They’re usually relativelynarrow and disperse quickly in deeperwater. Once you’re out you can resumeyour original course, though you’ll be fur-ther from shore. Never try to swimdirectly against a rip current.

When diving in current from a boat, yougenerally begin your dive swimming intothe current, so that it’s pushing you backto the boat when you end the dive. If yout in a current, don’t fight it. At the sur-te your BCD, signal the boat to pick youst.

most currents you encounter come fromoffshore currents, which are permanente currents like the Gulf Stream, can alsoing. The earth’s rotation generates thesewhich makes them generally predictable,

though eddies and counter currents can cause localflow direction to change. Keep in mind that a cur-rent can sometimes change direction during your dive.

You’ll learn a bit more about currents later.

NorthernHemisphere

SouthernHemisphere

Equator Equator

Northern Hemisphere

Southern Hemisphere

Equator Equator As the world turns.The earth’s rotationgenerates permanent, largescale currents. They’regenerally predictable,though eddies and countercurrents can cause localflow direction to change.

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Upwelling. An upwelling is a slow-moving cur-rent commonly caused by offshore winds push-ing the surface water away from shore. As thesurface water moves out to sea, deep waterflows up to take its place. The deeper water isusually clear and cold, creating excellent,though cooler, diving conditions.

Out of the deep.An upwelling is a slow-moving current commonlycaused by offshore winds pushing the surfacewater away from shore. As the surface water movesout to sea, deep water flows up to take its place.

Tides. The water level in the oceans and seas(and even some very large lakes) rises and fallsin a daily cycle called tide. The moon and suncauses tide as their gravity pulls on the water, cre-ating a bulge that, from our perspective, movesacross the oceans as the earth turns. Tides vary intheir time and height from place to place due togeographic configuration. They affect dive condi-tions — sometimes improving them, sometimesworsening them — by producing currents, changingdepth and changing visibility.

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144

MOON

EARTHSUN NEAP TIDE

Outer space influence.The moon and suncause tides as theirgravity pulls on thewater, creating a

Before diving, check local tidetables and become familiar withhow tides affect local conditions.

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As a general guideline, the best diving conditions occur at high tide.

SPRING TIDES

bulge that, from ourperspective, movesacross the oceansas the earth turns.Dive Planning

Dive planning avoids disappoint-ments due to misunderstandingswith your buddy, forgotten equip-ment or poor dive site conditions
— it’s really planning your fun. You can think of dive planning infour steps : advance planning,
Open Water Diver Manual

1. ________ create surge,which you avoid by ______.a. Tides, avoiding high tide.b. Waves, going deeper.c. Tides, going deeper.d. Waves, staying shallow.

2. Longshore currents tend to:a. push you parallel to theshore.b. carry you seaward.c. None of the above.

3. Waves breaking off shoreindicate:a. a coming change in thesurf conditions.b. an upwelling.c. a rip tide.d. None of the above.

4. You can recognize a rip cur-rent by:a. turbid, foamy water.b. strong flow away fromshore.c. disruption of the waves.d. All of the above.

5. If caught in a rip, you should:__________________________________________________________________

6. An upwelling tends to cause__________ dive conditions.a. poorb. excellentc. unpredictable

7. Tides affect diving conditionsby (check all that apply):a. causing currents.b. affecting visibility.c. generating rip currents.d. causing upwellings.

8. Generally, the best tidal levelfor diving is:a. low tide.b. high tide.

How’d you do?1. b. 2. a. 3. d. 4 d. 5. swim parallel to shore. 6. b.7. a, b. 8. b.


In this subsection on The Dive Environment,you learned:

▲ Temperature, visibility, water movement,bottom composition, aquatic life and sun-light affect dive conditions.

▲ A thermocline is an abrupt transition tocolder water.

▲ Plan your dive accounting for the watertemperature at your planned depth.

▲ When possible, use a visual reference fordescending and ascending.

▲ When diving with a current present, headinto the current during the dive.

▲ If caught in a current, don’t fight it. Swimacross the current, or establish buoyancyand signal for assistance.

▲ Avoid bottom contact by staying neutrallybuoyant.

▲ Most aquatic life injuries result from care-lessness — watch where you put yourhands, feet and knees.

▲ Wear gloves and an exposure suit toreduce the likelihood of aquatic life stingsand cuts.

▲ Sunburn is entirely avoidable.

▲ Surf diving requires special training andtechniques.

▲ If you get caught in a rip current, swimparallel to shore until you’re out of it.

Summary PointsSummary Points

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preparation, last-minute preparation and pre-dive planning.

Advance Planning
Planning a dive starts when you decide to godiving. At this stage, you generally: select abuddy (or vice versa), establish a dive objec-tive (i.e., agree on what you’ll do on the dive),choose a dive site (may be a general choice atthis stage), determine the best time to diveand discuss logistics (agree on where/when tomeet, etc.) with your buddy.
It’s a good idea to agree on a common objec-tive to avoid misunderstandings. If you showup with camera gear and your buddy arriveskitted up for search and recovery, one of youwon’t be doing what you planned.

If necessary, you can check your log book forrelevant information about the site if you’vebeen there before. Plan an alternate dive sitein case you can’t dive at your primary site(poor conditions, speed boat competition, ex-spouse is there, etc.). Decide on the best timeto go, which the tides and other activities inthe area may influence. Finally, discuss logis-tics, such as when to leave for the dive, howto get there, what to take and emergency con-tact information.

PreparationIt’s a good idea to start preparing for a diveat least a day or two ahead of time. Inspectall the equipment you’ll be using, make sureyour tank is filled, gather your equipmentinto one place and use an equipment check-list to make sure you’ve got everything.(There’s a sample checklist in the Appendix.)Check your equipment while you have ampletime to fix or replace anything broken, miss-ing or that your dog chewed on. If possible,check local information sources like televi-

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146

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sion, radio, your dive center, etc., for a report on divesite conditions.


31. You need to plan your divesfor what three reasons?

32. What are the four stages ofproper dive planning?

33. What five general steps do youfollow during the advancedplanning stage of dive plan-ning?

34. What four general steps doyou follow during the prepara-

MAINObjectives
Last-minute Preparation
Just before you leave for the dive:

1. Check the weather report.2. Let someone who isn’t going with you know about

your planned dive, including where you went, whenyou expect to be back and what to do if you’redelayed. Include your mobile phone number if youtake one with you.

3. Gather those last-minute type items like a jacket,hat, sunglasses, wallet, lunch, ice chest, certificationcard, log book, etc.

4. If you haven’t yet, pack your gear bag; if you’re boatdiving, pack so the first thing in is the last thing out.

5. Make an “idiot check” so that you don’t leave any-thing behind and show up with, say, only one fin.

Predive PlanningAt the dive site, you plan the details. It’s best to do thefollowing before you start putting your gear together:

1. Evaluate the conditions. Take your time, especially ifyou’re watching wave patterns.

tion stage of dive planning?

35. What five steps do you followduring the last-minute prepara-tion stage of dive planning?

36. What seven steps do you fol-low during the predive plan-ning stage of dive planning?

2. Decide whether or not conditions favor the dive andyour objective. If they don’t, go to your alternate site,and if conditions are bad there, too, pull the plug.Diving’s supposed to be fun; if it’s not going to befun, do something else.

3. Agree on where to enter, the general course to follow,the techniques to use on the dive and where to exit.

4. Review hand signals and other communications.5. Decide what to do if you become separated.6. Agree on time, depth and air supply limits.7. Discuss what to do if an emergency arises.

The idea in predive planning is to anticipate, discussand agree on as much as possible before you get in thewater.


You can’t plan by accident.Think of planning your dive as planning your fun –and safety. No one can plan a dive and follow thatplan for you – you and your buddy have to do it.

Dive the PlanIt doesn’t make much sense to form a dive plan, thennot use it. You have more fun and fewer problemswhen your dive follows what you agreed upon. You’llget what you want out of the dive when you and yourbuddy understand what to do when because you dis-cussed it before the dive. By following a solid diveplan, you’re much less likely to run into any hazards,and more likely to handle them if you do.

A dive plan does not have to be complicated, nor doesit need to take a lot of work, nor does it need to beinflexible. It can be very simple, take only a couple of

minutes to discuss, and offer plenty ofoptions depending on what you find under-water — but you should follow it.

Get the most out of diving by planning your divewith your buddy, and then diving the plan. This isimportant for your safety and fun – no one can plan adive and follow that plan for you – you and yourbuddy have to do it.

Boat Diving

1. Planning your dive helps avoid dis-appointments due to misunder-standings, forgotten equipment, orpoor site conditions.True False

2. You can divide dive planning intoadvanced planning, preparation,last minute preparation and prediveplanning.True False

3. Steps in advanced planning include(check all that apply):a. choosing a buddy.b. agreeing on an objective.c. agreeing on logistics.d. reviewing hand signals.

4. In the preparation stage, you don’tneed to inspect your equipment.True False

5. Last-minute preparation includes(check all that apply):a. letting someone know whereyou’re going and when you plan toreturn.b. packing items like ice chests,jackets, etc.c. checking the weather.

6. If you find conditions poor at yourdive site:a. be brave and dive anyway.b. try your alternate site. Otherwise,


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Chances are, you’ll make a lot of dives from boats. Inmany areas, it takes a dive boat to reach the siteswith the best clarity, the most aquatic life, and themost interesting reefs. Boats take you to dive sitesinaccessible from shore, and in some places you reachall or most dive sites only by boat. Boat diving elimi-nates long, tiresome surface swims, dealing with surf,and hikes to and from the water. Beyond all this, it’sfun to go boating with other divers. You get to knownew people, sight see on the way to and from the divesite, and generally enjoy the whole experience.

cancel the dive.

How’d you do?1. True. 2. True. 3. a, b, c. 4. False.5. a, b, c. 6. b.

Before heading out on a boat, spend some time get-ting ready:

1. Inspect your equipment for potential problems, fillyour tank and pack spare parts. Once you’re out

Chapter Three 147


Underline/highlight theanswers to these questions as you read:

37. What are three benefitsof diving from a boat?

38. When preparing for aboat dive, what five gen-eral considerations applyto equipment prepara-tion?

39. Before a boat dive, whatfour general considera-tions for personal prepa-ration apply?

40. What part of the boat is:• bow (forward)?• stern (aft)?• starboard?• port?• leeward?• windward?• bridge?• head?• galley?

41. By what four ways canyou minimize the effectsof motion sickness whileon a boat?

MAINObjectives

Cast off!It’s fun to go boating with other divers. You get to know new people,sight see on the way to and from the dive site, and generally enjoy thewhole experience.

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there, missing or broken gear oftenmeans you miss the dive. Havingspares can make you immenselypopular with other divers who needsomething but don’t have theirown spares.2. Be sure you’ve marked your

stuff so it doesn’t get confusedwith someone else’s on acrowded boat.

3. Use a dive bag for carryingyour equipment to and from theboat.

4. Pack your equipment so whatyou need first ends up on top.

5. Take ample warm/dry clothing,as appropriate for the region.Be prepared because in manyplaces, it’s common to experi-ence abrupt weather changesout on the water.

Prepare yourself as well as yourequipment. Be well rested, espe-cially if the boat departs early. It’sbest to avoid excessive alcohol thenight before, and avoid foods youdon’t digest well. It’s important tobe well hydrated with lots of wateror juices. Make sure you have yourticket, money, lunch and warmclothes, etc. all rounded up as necessary.

If you’ve not spent much timearound boats, you’re going to wantto learn some new terms so thatwhen the captain says, “the head isforward, on the portside o’ the gal-ley and aft o’ the wheelhouse,mate,” you don’t respond, “Eh?”

The bow is the front of the boat,

Easy as she goes.Typical charter dive boat layout.

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and the rear is called the stern. Going towardthe bow is going forward, and aft is towardthe stern. The port side of the boat is theboat’s left when you stand facing the bow. Thestarboard side is the right. (To help youremember, “port” and “left” have the samenumber of letters. Think of “left port.”)

When the wind blows across the boat, thewind comes from the windward side and theside away is the leeward (pronounced “loo-ard” in many areas) side. A boat’s bathroom iscalled the head, and the kitchen is called the galley. Thesteering wheel is the helm, which is found on the bridge.The bridge is often in the wheelhouse, a cabin with all thecontrols that make the boat do what the captain wants (most of the time).

On charter boats, you may find areas off-limits, or just off-limits when you’re wet. Check with the crew or captainbefore entering the bridge, galley or sleeping area whenyou’re wet.

Try to arrive at least a half hour before departure. Thisgives you time to check with the crew, sign in and secureyour dive equipment. On some charter boats, you’ll alsopick out a bunk or a cabin space to stow your dry clothesand personal items.

You need to think about seasickness before it happens.Seasickness is like sunburn in that it’s one of those thingsthat makes you absolutely miserable, but you can take pre-cautions. So if you may be prone to seasickness, avoid it bytaking seasickness medication (as advised by your physi-cian) before you get underway and avoid greasy foods priorto boarding.

Underway, stay in the fresh air on deck and out of the boatexhaust. It helps to stay in the center of the boat, whichmoves the least, and watch the horizon. Try to stay busysetting up your equipment so you’ll be prepared to enter thewater as soon as possible. Reading and intricate tasks tendto promote seasickness, so leave the needlepoint at home.

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If you do get sick, go to the leeward side (wind at your back)and have someone come with you (no joke — to hold on to

you for safety when you lean over the side). Stayout of the head (that’s about the worst place to go),and try to relax. To avoid seasickness, many diverstake seasickness medication if it might be a prob-lem — check with your physician or pharmacist ifyou need a recommendation on the type that’s bestfor you.

The ride to the dive site can take minutes or hours,depending on where you are. Once the boatanchors at the site, diving begins only after thecaptain or crew give the okay. Typically a crewmember briefs you about dive procedures, whichyou’ll need to listen to closely. Pay attention tocrew briefings, because they include importantinformation you’ll use to plan your dive with yourbuddy, such as current strength and direction, thedepth, emergency procedures and similar informa-

tion. If you fail to pay attention to crew briefings, you canput yourself and your buddy at risk.

As you gear up, be careful with heavy equipment. On apitching boat, it’s easy to lose your balance and hurt your-self, and dropping tanks or weight belts can damage thedeck. When putting on your scuba unit, get someone toassist you and help you stay balanced. Many dive boatshave benches and racks that make it easy to slip into yourgear while seated. To don a weight belt, step over it ratherthan swing it around your waist.

Be careful walking with equipment on. Equipment changesyour center of gravity and makes your balance awkward, allthe more difficult if the deck is slippery and the boat rolls. Ifnecessary, hang onto railings and handholds as you move,and don’t try to walk with fins on. Put your fins on immedi-ately before entering the water, using a rail or your buddyfor balance.

When you and your buddy are ready to enter, check with thedivemaster or a crew member, and enter where they tell you


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to. The most common entry when you dive from large diveboats is the giant stride, but from smaller vessels you mayuse a controlled seated entry or a back roll. If you have aphysical challenge that requires a different entry, let thecrew know so they can accommodate you. Be certain theentry area is clear before entering.

If you’re using a camera or other accessory, don’t enter thewater with it. Have someone hand it to you after you get in.Note the current direction so you can swim into it on thebottom, and then descend, preferably along the anchor lineor other descent line to the bottom. On the bottom, get yourbearings and swim into the current. Plan your dive andnavigate so you finish near the boat with enough air soyou’ll be back on board with 20-40 bar/300 to 600 psi left inyour tank. If there’s a current, you’ll find it easiest toascend the anchor line, which keeps you from being carriedpast the boat.

If you hear the boat’s underwater recall during thedive, remember to surface and look toward the boatfor instructions, or as they direct during the briefing.

At the end of the dive, you usually surface in front ofthe boat, keeping one hand over your head for pro-tection. When you break the surface, establish buoy-ancy and signal to the divemaster or crew thatyou’re okay. Avoid swimming back to the boat imme-diately below the surface because if there are otherboats underway in the area, they will not be able tosee you. If you’re at the surface away from the boat,watch out for boat traffic. You can use an inflatablesignal tube, whistle or other signalling device toattract the attention of the dive boat, or of otherboats that might not see you.

It’s not very likely, but if you surface and the boat’s not insight, stay calm and get buoyant. The boat may haveslipped anchor or the captain may have needed to leave foran emergency. Relax and wait to be picked up. If the shoreand a reasonable exit area are close, slowly swim in thatdirection.

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When you reach the boat’s exit area, don’t crowdit. Exit one at a time and stay clear of diversclimbing the ladder ahead of you because theycan fall, drop a weight belt or have a tank sliploose, which you wouldn’t enjoy one bit if you’redirectly beneath. Hand accessory equipment upbefore climbing the ladder, but keep all yourother equipment in place until you’re aboard(mask on, breathing from snorkel or regulator,etc.) You’ll usually need to take off your fins, butdon’t do so until you have a firm hold of the boat,because a current can carry you away from it andwithout your fins, you’dhave difficulty swimmingback. When wearingadjustable strap fins, youcan slip the fins over yourwrist so that if you did loseyour grip, you’d be able to pull them back on and swim.

Once aboard, clear yourstuff off the deck. A clut-tered deck can cause peopleto trip, and stuff gets bro-ken when divers step on it.Stow your gear directly intoyour equipment bag as youremove it, secure your tankand store accessories appropriately.

After the last dive, try toget your gear packed beforethe boat gets underway,since it’s usually easier topack at anchor. On a char-ter boat, pay attention tocrew directions regardingpre and post dive roll calls,equipment stowage andother instructions.


1. Benefits of diving from a boatinclude (check all that apply):a. reaching dive sites inac-cessible from shore.b. avoiding long surfaceswims.c. fun.

2. In preparing your equipmentfor a boat dive, you’ll want to(check all that apply):a. inspect it.b. use an equipment bag.c. make sure everything’smarked.d. include appropriate cloth-ing when you pack it.

3. To be ready for a boat dive,you should (check all thatapply):a. be well rested.b. avoid excessive drinkingthe night before.c. eat a heavy meal.d. pack your bag so that whatyou need first is on top.

4. The ________________ isthe front of the boat; the______________ is the bath-room.a. bow, starboardb. stern, galleyc. bow, galleyd. bow, head

5. To minimize motion sickness(seasickness) you maychoose to (check all thatapply):a. take seasickness medica-tion.b. stay in fresh air on deck.c. look at the horizon.d. stay near the center of theboat

How’d you do?1. a, b, c. 2. a, b, c, d. 3. a, b, d.4. d. 5. a, b, c, d.


Old salts.On your first few boat dives, watch experiencedboat divers and learn from them. Boat divingprocedures are mostly common sense and notparticularly difficult, and they allow boat dives torank among your best dive experiences.

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On your first few boat dives, watch experienced boat diversand learn from them. Boat diving procedures are mostlycommon sense and not particularly difficult,and they allow boat dives to rank among your best dive experiences.

Diving enjoys a safety record better thanmany other sports and adventure activities— but common sense tells you that whenyou’re under and in water, you face hazardsand risks. The guidelines and procedures youlearn in the course help you minimize andcontrol (but never completely eliminate)these risks, and you’ll find that if you andyour buddy dive within your limitations, planyour dives and follow safe diving practices,you’ll avoid problem situations. Keepingyourself physically fit and maintaining yourdive skills also play important parts in prob-lem prevention.

Nonetheless, if a problem does arise, you’llwant to be able to care for yourself and lendassistance to another diver. This sectionintroduces you to some of the basic conceptsof dive problem management. In this sectionyou’ll learn how to prevent and respond toproblems such as how to recognize when adiver needs assistance, how to assist anotherdiver, how to respond to problems underwaterand the basic procedures for emergencieswith an unconscious diver.

Keep in mind, though, that if you plan to dive where sec-ondary assistance (paramedic, lifeguard, divemaster orinstructor) is either remote (by time, distance or both) orcompletely unavailable, you should have additional trainingbeyond this course in first aid, cardiopulmonary resuscita-tion (CPR) and diver rescue. CPR and first aid training pro-vide skills that can help others no matter where you are,

Problem Management

Chapter Three 153

In these subsections on Dive Planning andBoat Diving, you learned:

▲ Planning your dive plans your fun.

▲ A dive plan doesn’t have to be complex,nor take a lot of time, nor be inflexible,but you do need to follow it.

▲ Boat diving has many benefits that makeit popular.

▲ You want to inspect and pack your gearappropriately before a boat dive.

▲ Different parts and areas on a boat havenautical terms you should know.

▲ Be careful when moving around on arolling boat with your gear on.

▲ Listen to crew briefings about proce-dures, where to enter and exit the water,and other techniques and emergencyconsiderations.

▲ Don’t get under another diver who’sclimbing the boat ladder.

▲ You may choose to avoid seasickness bytaking seasickness medication.


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making them worth having apart from diving.The Emergency First Response course offeredby PADI trains you in CPR and first aid emer-gency care. Emergency First Response is avail-able through PADI Professionals, Dive Centersand Resorts.

To learn how to handle the specific and poten-tially complex problems unique to diving, planto complete the PADI Rescue Diver course. TheRescue Diver course makes you a more capablediver by expanding and refining your problemprevention, management and handling skills.Although it covers a serious subject, and it ischallenging, most divers cite the Rescue Divercourse as one of the most rewarding coursesthey’ve taken.

But for now as a diver, you need to emphasizeproblem prevention and be prepared with emer-gency contact information: phone numbers forlocal paramedics and police, radio frequenciesfor Coast Guard, contact information for areadiver emergency services like the Divers AlertNetwork (DAN) and the Diving EmergencyService (DES). In areas that lack diver emer-gency services, have the number and contactinformation for the nearest recompressionchamber and emergency medical services. Carrychange, a phone card, a mobile telephone, orwhatever is appropriate so you can contact helpin an emergency. Your instructor will give youemergency contact information specific to thearea where you’ll be diving.

Surface Problem Management


Serious fun.To learn how to handle the specific andpotentially complex problems unique to diving,plan to complete the PADI Rescue Diver course.Most divers cite the Rescue Diver course as oneof the most rewarding they’ve taken.

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Considering that you scuba dive under-water, it may seem odd that the majorityof diver distress situations take place at the sur-face, but that’s exactly what happens. You cancontrol or prevent surface problems by divingwithin your limitations, by relaxing while youdive and by establishing and maintaining posi-tive buoyancy when you’re on the surface.

Possible surface prob-lems include overexer-tion, leg muscle crampsand choking on inhaledwater. You’ve alreadylearned about handlingoverexertion, and as yourecall, if you choke onwater, you hold yourregulator or snorkel in place and coughthrough it — keep it inyour mouth, and keepyour mask on. Swal-lowing sometimes helpsrelieve choking, too. Besure you have sufficient buoyancy, because coughinglowers your lung volume, decreasing your tendency to float.


42. By what three ways can youprevent or control mostdive problems that occur atthe surface?

43. What should you do if a div-ing-related problem occursat the surface?

MAINObjectives

1. You can prevent and control mostproblems at the surface by (checkall that apply):a. establishing positive buoyancy.b. diving within your limits.c. relaxing while you dive.

2. If you have a problem at the sur-face, you should (check all thatapply):a. establish positive buoyancy.b. ask for help.

How’d you do?1. a, b, c. 2. a, b.

QUICKQUIZSelf Assessment 12

Can you lend a hand? Divers who have a problem, but who are incontrol of their actions normally appearrelatively relaxed and breathe normally.Typically, they signal for help if appropriate,keep their equipment in place, move withcontrolled, deliberate movements, andrespond to instructions.

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If you have a problem at the surface, immediatelyestablish buoyancy by either inflating your BCD ordropping your weights. Let your equipment do thework — having to swim, tread water or otherwisehaving to fight to stay above water exhausts youquickly. Don’t hesitate to discard your weights if you can’t stay up with your BCD; weights are easilyreplaced.

Stop, think, then act. Need help? Ask! Whistle, waveand yell. It’s the smart, safe thing to do. Get helpwhen you need it, before a small problem becomes abig one, and you make it easier on yourself and otherdivers. Divemasters will tell you it’s not the peoplewho ask for assistance who give them gray hair —it’s those who need it and don’t ask.

Problem RecognitionBefore you can help another diver, you have to recog-nize that the diver needs help, then follow your recog-nition with appropriate action. Divers who have aproblem, but who are in control of their actions, look

Chapter Three 155

pretty much like divers without problems. Generally, ifthey need help, they signal for it. Divers in control nor-mally appear relatively relaxed and breathe normally.Typically, they keep their equipment in place, movewith controlled, deliberate movements, and respond to instructions.

156

Underline/highlight the answer question as you read:

w do the appearance andtions of a diver who isder control differ from appearance and actionsa diver who has, or isout to have, a problemolving panic?

MAINObjectives

CKSelf Assessment 13

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Divers who have a problemand panic lose self control,and sudden, unreasoned fearand instinctive inappropriateactions replace controlled,appropriate action. Panickeddivers, fearing drowning, typi-cally struggle to hold theirheads high above the water,expending tremendous energy. Theyusually fail to establish positive buoy-ancy, and spit out their regulatorsand shove their masks up on theirforeheads, requiring them to fighteven harder to breathe. Panickeddivers will generally be anxious andbreathe rapidly and shallowly. Theypay no attention to their

buddy or others and make quick, jerkymovements. Their eyes are wide and unsee-ing, and they don’t usually respond to direc-tions. Divers exhibiting these signs needimmediate help, because they will continueto struggle until completely exhausted andunable to remain afloat.

to this

44. Hoacuntheof abinv

QUIQUIZ

Red alert! Panicked divers, fearing drowning, typicallystruggle to hold their heads high above thewater. They usually fail to establish positivebuoyancy, and spit out their regulators andshove their masks up on their foreheads.They pay no attention to their buddy orothers and make quick, jerky movements.Their eyes are wide and unseeing, and theydon’t usually respond to directions.

Assisting Another DiverThere are four basic steps to assistinganother diver: 1) establish ample buoyancy(for both of you), 2) calm the diver, 3) helpthe diver reestablish breathing control and4) if necessary, assist the diver back to theboat or shore.

Always begin with buoyancy — you reducethe immediate risk by assuring that neither


1. Panicked divers typically (check allthat apply):a. drop their weights and establishpositive buoyancy.b. push off their masks and spit outtheir regulators.c. respond to instructions.d. need immediate help.

How’d you do?1. b, d.

of you will sink. To do this, ideally throw orextend some flotation to the diver, but if youcan’t do that, inflate the diver’s BCD and/or dis-card the weights. Once you’ve established buoy-ancy, calm the individual by talking, offeringencouragement and persuading the diver to

relax and take it easy.

Have the diver take deep,slow breaths to reestablishbreathing control, andencourage relaxation andself-control. After sometime to rest and recover, if necessary assistthe diver using the tank valve tow or themodified tired-swimmer carry, which you’llpractice during Confined Water Dive Three.

Underwater Problem Management

Underwater, overexebecause breathing ras you go deeper. Ovlike your regulator idemanding more airvent overexertion (aactivity and by paci


45. What are the four basicsteps to assisting anotherdiver?

MAINObjectives

Enjoy the ride.After some time to rest and recover, if necessaryassist the diver using the tank valve tow or themodified tired-swimmer carry.

To the rescue.The fastest and preferred method for helping adiver establish buoyancy is to throw the diversomething that floats, preferably on a line so you can gently pull the diver to you.

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You can prevent or control underwater prob-lems by 1) relaxing while you dive, 2) keep-ing close watch on your air supply and 3)diving within your limitations. Of the fewproblems that do occur under water, themost likely are overexertion, running out of or low on air, regulator free flow andentanglement.

Overexertion. In Section Two, you learned toprevent overexertion by moving and breath-ing slowly and deliberately, and by pacingyourself. You also learned that if you do getoverexerted, stop all activity, rest, relax andbreathe slowly until you restore your normalbreathing pattern.

rtion can give you a feeling of air starvationesistance through the regulator increases erexertion is the problem, but it may feel sn’t delivering enough air. Actually, you’re than it can deliver — as you recall, you pre-nd air starvation) by avoiding strenuousng yourself.

Chapter Three 157

Running low on or out of air. Running out of air is probablythe easiest problem to avoid, and air stoppage due to a mal-function is extremely remote (more about this in a moment).To keep from running excessively low on or out of air, make ahabit of checking your SPG frequently. Obviously, your SPGonly works if you look at it.

But suppose the unlikely happens and your air either runsout or stops unexpectedly. It’s still not a serious situation ifyou take a moment to consider your options and then actintelligently. Here are five options you can consider in a low-air situation, in their order of priority:

1. Make a normal ascent. Do what? No, it’s not as odd as itsounds. If you’re very low on air (you feel resistance andhave to pull hard, but you’re still getting something), yourtank isn’t completely empty. As you ascend, the waterpressure surrounding you decreases, so more of theremaining air in your tank becomes usable. Breathinglightly (but continuously), you can make a controlled, con-tinuous ascent to the surface.

2.

3.



46. By what three ways can youprevent or control most diveproblems that may occurunderwater?

47. What are four problems thatmay occur underwater?

48. What, in order of priority, arethe five low-on-air/out-of-airemergency procedures?

49. How do you breathe from afree-flowing regulator?

50. What should you do if youbecome entangled underwater?

MAINObjectives

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Ascend using an alternate air source. Think of this as yourbest all-round choice when you’re out of air. But for this towork, you must know how to locate your buddy’s alternate,how to secure it and how to use it. Don’t neglect thesesteps in your predive safety check.

Ascend using a controlled emergency swimming ascent.Supposing you’re completely out of air and your buddy istoo far away to provide an alternate air source (What didyou learn about staying close to your buddy?) and thewater is 6 to 9 metres/20 to 30 feet deep or less, you maydecide to make a controlled emergency swimming ascent.This simply involves looking up and then swimming to thesurface, exhaling continuously while making an aaaahhhsound into your regulator to release expanding air and toprevent lung over expansion injury. Upon reaching thesurface, orally inflate your BCD for positive buoyancy. Theemergency swimming ascent isn’t difficult and you’ll havea chance to practice during your third confined water dive.

4. Buddy breathe with a single regulator. Buddy breathing,which is sharing a single second stage between two divers,was once a standard air-sharing method, but became lessand less favored as a viable option over the last 20 years.Alternate air sources have made buddy breathing unneces-sary, along with the fact that buddy breathing is a moder-ately complex motor skill to perform in an emergency.

If you’re deeper than 12 metres/40 feet and there’s no alter-nate air source available, buddy breathing may be an option ifyou and your buddy remain calm, and if you’re both trainedand practiced with it. Once you begin buddy breathing, youand your buddy should continue all the way to the surfacewithout attempting to switch to another out-of-air option. Yourinstructor may have you practice buddy breathing, but keep inmind that sharing air with an alternate air source is far morepreferable and makes buddy breathing an unnecessary option.

5. Make a buoyant emergency ascent. You’re too deep for acontrolled emergency swimming ascent and you’re too farfor your buddy to help you. You can still make it to the sur-face, though the situation isn’t ideal. You make a buoyantemergency ascent, just like a controlled emergency swim-ming ascent, except you drop your weights. You look up andexhale continuously, making the aaaahhh sound into yourregulator as you rise to the surface. You’re going to exceeda safe ascent rate, and that has some serious risks — souse this method only when you doubt you can reach thesurface any other way. You can flare out to create drag andhelp slow your ascent if you start to rise faster than neces-sary to reach the surface safely.

After reaching the surface using any of these options, remem-ber that you may need to inflate your BCD orally to establishpositive buoyancy. Remember to discuss out-of-air emergencyoptions with your buddy as part of planning your dive, andstay close together so you can assist each other if necessary,especially as you go deeper. Look after one another, watchingyour air supplies, breathing patterns, and time and depth lim-its. By remaining alert and monitoring each other, you canavoid air supply and other problems.

Chapter Three 159

Sing all the way to the surface.A controlled emergencyswimming ascent involveslooking up and then swimmingto the surface, exhalingcontinuously while making an“aaaahhh” sound into yourregulator to release expandingair and to prevent lung overexpansion injury.

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Regulator free flow. Today’s regulators are extremelyreliable; it’s highly unlikely that a regulator malfunc-tion would cut off your air. Besides this, they’redesigned to fail-safe, that is, most malfunctionsresult in an air free flow rather than no air. You canbreathe from a free-flowing regulator by following acouple procedures.


1. You can prevent or control mostdive problems underwater by(check all that apply):a. relaxing while you dive.b. watching your air supply.c. diving within your limitations.d. maintaining a brisk pace.

2. Problems that can occur underwa-ter include (check all that apply):a. overexertion.b. regulator free flow.c. entanglement.d. running low or out of air.

3. The general best all round option ifyou run out of air is:a. buddy breathing.b. buoyant emergency ascent.c. controlled emergency swimmingascent.d. None of the above.

4. To breathe from a free flowing reg-ulator (check all that apply):a. don’t seal your lips around themouthpiece.b. allow excess air to escape.

5. If you become entangled underwa-ter, your first response should be:a. to slowly untangle yourself.b. to cut yourself free.

How’d you do?1. a, b, c. 2. a, b, c, d. 3. d. The bestall round option if you run out of air isto ascend using an alternate airsource. 4. a, b. 5. a


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First, don’t seal your mouth on the regulator becausethe continuous flow could, in the worst case, cause alung over expansion injury, but more likely it wouldmake the regulator pop out of your mouth and floodyour mask. Instead, hold the regulator in your handand press the mouthpiece to the outside of your lips,inserting one corner if you like. Breathe the air youneed like drinking from a water fountain, letting theexcess air escape.

You should begin your ascent immediately if yourregulator free flows because you’ll exhaust your airsupply quickly. When you reach the surface, turn offthe air and don’t use the regulator until it has beenserviced by a qualified technician. If you maintainyour regulator properly, keep it out of the sand ordebris and have your PADI Dive Center or Resortservice it annually, you’ll probably never have a free-flow problem.

Entanglement. As mentioned earlier in the discus-sion on aquatic plants, entanglement is rare. Besidesplants, though, fishing line, tree branches, loose lineand old fishing nets have the potential to causeentanglement problems. Prevent entanglement bymoving slowly, watching where you go and keepingyour equipment secure so it doesn’t snag or tangle.

As long as you have air and are unhurt, entan-glement really isn’t an emergency. Stop, think,and then work slowly and calmly to free your-self. Get your buddy to help you, and don’t twist orturn because this usually wraps line around you andworsens the tangles. If your scuba unit is tangled,you may have to remove it, keeping your regulator in

your mouth, free it, and then put it back on. (Youwill practice taking your unit off and putting it backon underwater in Confined Water Dive Five.) Ifyou’re low on air, or you’re severely entangled, youmay need to use your knife to cut yourself free; if so,do so carefully — don’t complicate the situation byinjuring yourself or cutting a piece of gear. And, withtough rope, cutting may be slower than disentan-gling — use what works fastest. In any event, entan-glement isn’t common, and more of an irritationthan a serious problem if you deal with it calmly.

Near Drowning and the Unresponsive DiverNear drowning occurs when someone revives a diver(or swimmer) who became unresponsive (uncon-scious, or unable to respond or act coherently) andstopped breathing while submerged. Swallowingwater, extreme fatigue, entanglement and lung overpressurization may be the cause, with panic, ineffi-cient breathing, throat blockage, exhaustion, heartstoppage and unconsciousness contributing.

With an unresponsive diver, the primary concern isto check for breathing and to begin rescue breaths if

Underline/highlight the answer to this ques-tion as you read:

51. What are the four general procedures fordealing with an unresponsive diver in the water?

MAINObjectives

Breath is life.With an unresponsive diver, the primary concern is tocheck for breathing and to begin rescue breaths if thediver isn’t breathing.

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the diver isn’t breathing. If a diver is unresponsiveunderwater, bring the diver to the surface; someonemay need to perform rescue breathing in the water,and if the victim has no pulse, CPR. You can’t per-form CPR effectively in water, so you need to get thediver out of the water.

Here are the four general procedures to follow if adiver appears to lose consciousness and becomesunresponsive in the water:

1. Quickly bring the diver to the surface and checkfor breathing.

2. Establish ample positive buoyancy for you andthe victim.

3. Get assistance as needed in providing rescuebreathing.

4. Help remove the diver from the water.

Chapter Three 161

Assistance continues once out of the water, with thefollowing steps also applying to a diver who, afterdiving, becomes unconscious or experiences symp-toms of lung over expansion injury. These symptomsmay include difficulty breathing, confusion, loweredalertness, a change in the level of consciousness,unclear thinking, visual problems, paralysis, andchest pain.

1. Keep airway open and check for breathing. Ifnecessary, start and continue rescue breathingand/or CPR.

2. Observe the diver constantly, checking breathingand pulse.

3. If the diver doesn’t require CPR or rescue breath-ing, keep the diver lying level on the left sidesupporting the head (called the recovery posi-tion). Don’t let this position interfere with trans-portation or other aid, and should not be used ifCPR is required. If the diver is responsive andmore comfortable lying prone, that’s fine.

4. Administer emergency oxygen if possible.5. Keep the diver still and maintain a normal body

temperature by protecting the diver from heat or cold.

6. Seek emergency medical assistance.7. If unable to accompany the diver to medical

treatment, write down as much backgroundinformation as possible and attach it to the diverin a conspicuous place.

Neutral BuoyancyBy now you’re aware that you need to maintainneutral buoyancy while diving to avoid bottom con-tact, so you can relax and maneuver easily, and soyou can prevent rapid, uncontrolled ascents anddescents. In the last confined water dive, youadjusted your weight for neutral buoyancy at thesurface. During this dive, you’ll develop your neutralbuoyancy skills further.

Confined Water Dive Preview


Supine is fine.If the diver doesn’t require CPR or rescue breathing,keep the diver lying level on the left side supportingthe head (called the recovery position). If the diver isresponsive and more comfortable lying prone,that’s fine.

1. If a diver becomes unresponsiveunderwater, you should:a. bring the diver immediately to thesurface and check for breathing.b. remove the diver’s tank.c. All of the above.

How’d you do?1. a.


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You’ve undoubtedly found that you needto use your BCD to trim and fine-tunebuoyancy when you descend and ascend,due to exposure suit compression, anddue to air compressing and expanding inyour BCD. When making changes to yourbuoyancy, whether adding or releasingair, do it slowly. Rapid changes make itdifficult for you to control buoyancy andcan lead to runaway ascents or descents.

You’ve probably been using mainly yourlow pressure inflator to fill your BCDunderwater. To orally inflate your BCDunderwater — which you might do if youhad a low pressure inflator problem forinstance, take your second stage in yourright hand and the BCD inflator in yourleft. Take a breath, remove the regulatorand blow about two thirds of this air intoyour BCD, operating the controls justlike you did when orally inflating it atthe surface. Save enough air to clear theregulator, and don’t forget to blow astream of bubbles as you switch backand forth — never hold your breath. Dothis until you’ve inflated the BCD suffi-ciently to attain neutral buoyancy.

Let’s look at the fin pivot method forestablishing neutral buoyancy. Thismethod guides you in getting the feel ofneutral buoyancy. You’ll practice doingthis several times in the course, usingboth your low pressure inflator and youroral inflator. When you use your low-pressure inflator, remember to add air inshort bursts. Don’t hold the button downcontinuously, and release air from yourBCD in small amounts, too.

Basically, here’s how you fin pivot: 1) lieface down on the bottom, 2) breathe

Chapter Three 163

In these subsections on Problem Management,you learned:

▲ Most problems occur at the surface.

▲ You prevent most problems by stayingrelaxed and diving within your limits.

▲ If you have a problem at the surface, estab-lish positive buoyancy and call for help if youneed it.

▲ A diver with a problem who is in control tendsto respond to instructions, and to establishbuoyancy.

▲ A panicked diver tends to spit out the regula-tor, push off the mask and to not to inflate theBCD nor drop weights.

▲ When assisting another diver, establish buoy-ancy, calm the diver, help the diver reestab-lish breathing control, and if necessary helpthe diver back to the boat or shore.

▲ If you watch your SPG, it’s highly unlikelyyou’ll run out of air.

▲ Using an alternate air source is your best all-round option when you’re out of air.

▲ You can breathe from a free-flowing regulatorby not sealing your lips on the mouthpiece.

▲ Entanglement isn’t a big deal if you reactcalmly and carefully untangle yourself.

▲ Bring an unresponsive diver immediately tothe surface, check for breathing and pulse,and begin rescue breathing and/or CPR asnecessary.

▲ Ask for help when you need it.


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slowly and deeply and 3) add air in smallamounts to your BCD (or dry suit – yourinstructor will give you more detail on this ifyou’ll be using a dry suit), gradually increas-ing your buoyancy until you slowly pivotupward on your fin tips as you inhale (buoy-ancy increasing with lung volume), andslowly pivot downward as you exhale (buoy-ancy decreasing with lung volume). Thismeans you’re neutrally buoyant at thatdepth and can fine-tune your buoyancy bycontrolling your lung volume. Be sure youdon’t hold your breath at any time.

If you have a physical challenge that makesit difficult to pivot on your fin tips, you canuse your knees or another contact point forpivoting. However, use your fin tips if youcan because it puts all your body mass onthe same side of the contact point; a contact


Here’s what you’ll be able to do when yousuccessfully complete Confined Water DiveThree:

1. Independently establish neutral buoyancyunder water by pivoting on the fin tips, or,when appropriate, another point of contact(both oral and low-pressure inflation).

2. Swim at least 10 metres/yards underwaterwhile maintaining neutral buoyancy.

3. Demonstrate the cramp removal technique.

4. At the surface in water too deep to standin, perform a tired diver tow for 25metres/yards.

5. React to air depletion by signaling out ofair, then securing and breathing from analternate air source supplied by a buddyfor at least one minute while swimmingunderwater.

6. Breathe effectively from a free-flowing reg-ulator for not less than 30 seconds.

7. Simulate a controlled emergency swim-ming ascent by swimming horizontallyunderwater for at least 9 metres/30 feetwhile continuously exhaling by emitting acontinuous sound.

Skill RequirementsConfined Water

Dive Three

Skill Requirements

Without LPI underwater.To orally inflate your BCD underwater takeyour second stage in your right hand andthe BCD inflator in your left. Take a breath,remove the regulator and blow about twothirds of this air into your BCD, operatingthe controls just like you did when orallyinflating it at the surface. Save enough airto clear the regulator, and don’t forget toblow a stream of bubbles as you switchback and forth.

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point that has body mass on both sides (likeyour knees — your lower legs, feet and fin areon the other side) may not set your buoyancyquite as accurately.

With practice, you’ll find it pretty easy tomaintain neutral buoyancy, to the point that itbecomes second nature. If it seems awkward atfirst, no worries. That’s normal. Keep in mindthat water’s density slows movement, sochanges in your buoyancy don’t seem to havean immediate effect. That’s why you add or

release small air amounts and wait a moment to see what hap-pens before adding or releasing more.

The volume of air in your BCD changes every time you changedepth. In shallow water, where air volume expands and com-presses the most for a given depth change, you’ll find buoyancycontrol the most critical — it’s actually easier as you go a bitdeeper, like in open water.

Don’t forget to adjust your buoyancy as you change depth, oryou may find yourself floating away from the bottom uninten-tionally. If this should happen, exhale and vent air from yourBCD, and swim downward. Some BCDs have extra exhaustvalves that allow you to dump air while swimming downwardat the same time. If you’re unable to and end up in a runaway

Chapter Three 165

Up and down.To fin pivot: 1) lie face down on the bottom, 2)breathe slowly and deeply and 3) add air insmall amounts to your BCD. Gradually increaseyour buoyancy until you slowly pivot upward onyour fin tips as you inhale. When you exhale,you should slowly pivot back down again.

Minor difference.If using a dry suit, you’lluse the low pressureinflator on your suitinstead of the one on your BCD to adjust yourbuoyancy for fin pivoting.

Protecting theenvironment.After you’ve establishedneutral buoyancy, yourinstructor will have youswim 10 metres/yards orfarther, remainingneutrally buoyant. Thissimulates how you swimavoiding damage to theenvironment when makingopen water dives.

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ascent, flare out facing the surface to create maximum dragand resistance and slow your ascent, while breathing continu-ously and maintaining normal lung volume. With experienceand by staying aware of your buoyancy, you should have few, ifany, runaway ascents.

During a normal ascent, keep your hand on the deflator, releas-ing small air bursts as needed to prevent excess buoyancy.When you reach the surface, immediately inflate your BCD andestablish positive buoyancy. You’ll have to pay close attentionto buoyancy control at first, but gradually it will become some-thing you do automatically.

Neutral Buoyancy SwimAfter you’ve established neutral buoyancy, yourinstructor will have you swim 10 metres/yards orfarther, remaining neutrally buoyant. Duringthis swim, pretend you’re swimming over a reefwith sensitive aquatic organisms and avoid anycontact with the bottom. This simulates how youswim avoiding damage to the environment whenmaking open water dives.

Cramp RemovalA cramp is a painful, involuntary muscle contraction, which, asa diver, you may experience in your leg or foot muscles. Severalthings can contribute to cramps: dehydration, working themuscle beyond its fitness level, restricted circulation, coldwater, and all of these working together. Your fins can con-tribute to cramping if the blade is too large for your legstrength, or if the foot pockets are too small and your feet don’tgo in them properly. Fitness, proper fin selection, practice,proper insulation and pacing your activity, will help you avoid cramps.

But they can happen anyway. Like most problems, it’s more ofan irritation than an emergency if you stop and think aboutwhat to do. For a cramp, stop and rest the cramped muscle.Stretch and gently massage it to increase circulation and pullout the cramp. If you have a leg cramp in your calf muscle, youcan stretch it by grasping the fin tip and pulling it toward youwhile you push with your leg. Your buddy can also brace the fintip for you.


Ow! To relieve a cramp, stop andrest the cramped muscle.Stretch and gently massageit to increase circulation andpull out the cramp. If youhave a leg cramp in yourcalf muscle, you can stretchit by grasping the fin tip andpulling it toward you whileyou push with your leg.

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After relieving the cramp, rest themuscle for a few minutes before con-tinuing at a slower pace — with about50 to 75 percent of the load you hadon the muscle before. A cramped mus-cle usually recovers better if youresume using it at a reduced paceafter a brief rest than if you stopusing it completely.

Tired Diver TowSometimes divers become so tired andout of breath they can’t swim to theboat or shore. Or, they may havesevere leg cramps that prohibit swim-ming. You can assist such a diver byestablishing positive buoyancy andhaving the diver do the same, then

helping the diver to the boat or shore using one of several tows,such as the tank valve tow or the tired diver push, sometimescalled the modified tired-swimmer carry. Your instructor willdemonstrate these and let you practice them.

Air Depletion/Alternate Air SourceCombined ExerciseDuring your first two confined water dives, youlearned how to use an alternate air source, andyou learned what it feels like to run out of air. Nowyou’re going to put these together to practiceresponding to running out of air. Your instructorwill turn off your air like when you did the airdepletion exercise. Don’t look at your SPG — butas soon as you feel breathing resistance, signal

“out of air” and “share air” to your buddy. Secure and startbreathing from your buddy’s alternate; after you take amoment to get situated and make contact with each other, yourinstructor will have you swim together for at least one minutewhile you continue to use the alternate. This simulates swim-ming to the surface from 18 metres/60 feet deep.

As soon as you secure your buddy’s alternate and remove yourregulator from your mouth, your instructor will turn your air

Chapter Three 167

Pull.Tank valve tow.

Push.Tired diver push,sometimes calleda modified tired-swimmer carry.

Thanks for the assist.As soon as you feelbreathing resistance, signal“out of air” and “share air”to your buddy. Secure andstart breathing from yourbuddy’s alternate air source.

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back on. That way, if you need to you can switch back to it.Confirm that the valve is open by checking your SPG, whichshould not be on (or near) zero if it is.

Free Flow Regulator BreathingEarlier you learned that it’s not likely that your regulator willfail so that it would cut off your air, but that a failure wouldmost likely cause an air free flow. You can breathe from a freeflowing regulator if you don’t seal your lips on the mouthpiece.During this confined water dive, your instructor will have youpractice breathing this way

Since your regulator probably won’t cooperate by spontaneouslymalfunctioning right when you need to practice this, you’ll simu-late the free flow by (you guessed it) holding in the purge button.

Remember to breathe without sealing your mouth on theregulator, “sipping” the air you need while allowingexcess air to escape. A free flowing regulator can reallyrush — don’t be surprised if it jostles and floods yourmask a bit. You’ll breathe from your simulated free flowfor at least 30 seconds, and your instructor may have youpractice turning off your air after surfacing like youwould with a real free flow. If you can’t reach your tankvalve unless you remove the scuba unit, do so for prac-tice. Although your buddy might do this for you, doing ityourself develops self-reliance. Check your SPG whenyou’re done; you’ll be amazed how much air a free floweats up in only 30 seconds — which is why you headstraight for the surface if it happens.

Controlled Emergency Swimming AscentAs you learned, the controlled emergency swimming ascent (also called CESA — pronounced “see-sa”) is one option if youlose your air supply at 6 to 9 metres/20 to 30 feet or less, and your buddy is too far away to provide an alternate air source(Buddy system, buddy system! You shouldn’t be that far fromyour buddy!).

Emergency swimming ascents are interesting because you startwith air in your lungs, exhale all the way to the surface and stillhave air in your lungs when you get there. This happensbecause air expands in your lungs as you ascend; the potential


Whoosh! You’ll simulate the free flowby holding in the purgebutton. Remember to breathewithout sealing your mouthon the regulator, “sipping”the air you need whileallowing excess air to escape.

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hazard is a lung over expansion injury, which you avoid by notholding your breath.

To make a controlled emergency swimmingascent, simply swim upward with all yourequipment in place, including your regulator.Look up, reach up and come up, swimming at18 metres/60 feet per minute or slower. Exhalethe entire time by making a continuousaaaahhhh sound through your regulator as you ascend.

By saying aaaahhhh, you exhale air at theright rate to prevent lung over expansion

injury, but you don’t exhale too much either. The idea is to main-tain a lung volume that is neither empty nor full.

Since you won’t be 9 metres/30 feet deep during your confinedwater dive, you’ll simulate the controlled emergency swimmingascent first horizontally, then diagonally from deeper to shal-lower water. You’ll have enough air in your lungs to swim a longway horizontally while exhaling continuously, but 9 metres/30feet will be ample for practice. After you do this horizontally, youcan be more than sure that you can do it vertically assisted byair expanding in your BCD and lungs. After an actual controlledemergency swimming ascent, you don’t feel out of breath — youstill have air in your lungs. You’ll get a chance to practice CESAvertically during your open water dives and may be surprisedhow much easier it is than simulating it horizontally.

Perhaps the greatest value of controlled emergency swimmingascent training is knowing you can do it. When you realize youcan reach the surface without difficulty, even if you suddenlylose your air supply, you can relax and enjoy diving more. Butwatch your SPG and stay close to your buddy so you never need to.

Now let’s start looking at what you’ll be doing during your openwater dives. Depending on the course location, schedule, yourpreferences and other logistical concerns, you may have alreadymade Open Water Dive 1, or may make Open Water Dives 1 and

General Open Water Skills

Chapter Three 169

Horizontal is vertical.Since you won’t be 9 metres/30 feet deepduring your confinedwater dive, you’ll simulatethe controlled emergencyswimming ascenthorizontally.

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2 after you successfully complete Confined Water Dive Three.You’ll do this if you’re completing only the Scuba Diver certifica-tion. Alternatively, you may make all your open-water dives aftercompleting all five confined water dives.

During your open water dives, you’ll apply and further develop theskills you’ve learned during the confined water dives, and you’llstart picking up some new skills that you can’t practically learn in a confined water environment. Skills in both categories mayinclude : 1) evaluating dive conditions, 2) gearing up for a dive in open water, 3) making entries and exits through mild surf,4) swimming on the surface and 5) descending/ascending in open water.

Evaluating Dive ConditionsWhen you arrive at a dive site, you want toknow whether the diving conditions arewithin your training and experience limita-tions. As you learned earlier, you normallycheck out the conditions before you gear up— no point unpacking and putting every-thing on only to find conditions don’t warrantdiving. Your instructor will show you how toaccount for considerations like weather,water temperature, bottom composition,

waves, depth, local area hazards and anything else that has directbearing on the dive. You’ll also preplan your entry and exit pointsand procedures as part of this evaluation.

Decide whether you can make the dive safely. Remember: Thisis your decision – you are ultimately responsible for yoursafety, and only you can make the final decision to dive. Ifyou don’t feel confident about it, your instructor may have youcheck your alternate site for acceptable conditions. If conditionsaren’t good, it’s best to go do something else — diving in poor orpotentially hazardous conditions isn’t fun. You’re doing this forfun, adventure and challenge — not to expose yourself to unrea-sonable risks.

Suiting UpIn the discussion on exposure suits you learned ways to avoidoverheating in your exposure suit as you get ready to dive. During


Diving report? When you arrive at a dive site, you want to determinewhether the diving conditionsare within your training andexperience limitations. Yourinstructor will show you howto account for considerationsthat have bearing on the dive.

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your open water dives, you’ll put this knowledge touse. Poor timing and sequence when you kit up cancause you to become somewhat frustrated, tired,breathless and overheated.

Ideally, you want to suit up so that you and yourbuddy finish simultaneously. This never happens, ofcourse, but you can time it so you’re both ready atabout the same time while staying cool and rested,ready to enter the water.

First, it helps if you checked and packed your equip-ment properly before the dive. Start putting every-thing together, but take your time and rest asneeded. In hot weather, cool off in the water if youneed to. Pace yourself with your buddy, but be asself-reliant and independent as possible, so youbecome familiar with your equipment.

As a suggestion, prepare and don your equipment like this:

1. Assemble your scuba unit. Prepare anything else that can bemade ready without putting your exposure suit on, such asdefogging your mask, adjusting any straps, etc.

2. Don your exposure suit. If it is a wet suit, put on pants andboots first, then the jacket and hood.

3. Put on your weight belt. With a few scuba units, you’ll put yourweight belt on after the unit. If you’re using an integratedweight system, it’s usually part of your scuba unit.

4. Have your buddy help you put on your scuba unit.5. Put on any wrist mounted gauges (often easier after putting on

your scuba unit so they don’t snag sliding into your BCD).6. Perform the predive safety check with your buddy.7. Don your mask and snorkel, which should’ve been adjusted

ahead of time.8. Put on your gloves.9. Finally, just before entering the water (boat diving) or in waist

deep water (shore diving) put on your fins; fins should’ve beenpreadjusted.

Suiting up requires thought at first, but after one or two dives,you’ll be more familiar with your equipment and it becomes second nature.

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One piece at a time.Suiting up requires thoughtat first, but after one or twodives, you’ll be more familiarwith your equipment and itbecomes second nature.

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Open Water EntriesEntry techniques vary from place to place according to the diveenvironment. If a dive site requires entry techniques that youdon’t know, always get an orientation to them so you can enter(and exit) safely. If your open water dives will be from shore, yourinstructor will teach you the proper entries for the dive site.

The following practices are generally recommended for most scubaentries from shore:

1. Have everything on before entering the water. Depending onthe environment and conditions, you may have your fins onwhen you enter the water, or you may carry them until reach-ing water about waist to chest deep.

2. As a general rule, breathe from your regulator until you’refloating in deeper water. This way, if you stumble, you can stillbreathe, even if you end up with your face in the water. Once indeeper water and floating with your BCD, switch to yoursnorkel to conserve air if you have a surface swim beforedescending.

3. If you’re walking in with your fins on, walkbackward or sideways and shuffle your feet.This helps you find obstructions or holes,scares away bottom-dwelling animals thatcould sting if you stepped on one, and helpsminimize the chances of falling. In some envi-ronments, however, you may want to avoidshuffling your feet because it will disturb thevisibility. Your instructor will teach you whichis appropriate for your open water dives.

4. Swim as soon as the water is deep enough.Swimming is often easier than wading.

Surf Entries and ExitsSurf entries and exits require special training and shouldn’t beattempted unless you have had that training. It is possible,though, that you’ll enter and exit through mild surf as part ofyour open water dives. Here are a few simple general procedures.

Entries. First, watch the waves and note where they’re breakingand how often. Do this during suiting up so you’ll be familiar withthe surf ’s pattern when you’re ready to enter.


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As you enter the water, breathe from your regulator. If wearingfins, walk backward, looking over your shoulder to watch whereyou’re going and to see oncoming waves. Your buddy should benext to you, and if you’re towing a float, it should be between youand the shore so a wave can’t push it into you. The idea is to getthrough the surf zone as quickly as possible.

When a wave is about to meet you, holdyour mask (so the wave doesn’t take it),stop, and lean into the wave as it hits you.It’s best to have your side to the waves,which presents less surface to it andaligns your legs for the best balance. Oncethe wave passes, move on again quickly. Assoon as the water is deep enough, beginswimming steadily and move quickly untilyou clear the surf zone, then rejoin yourbuddy if you became separated during the

entry. Be sure to keep a hand on your mask whenever you gothrough a wave, and until outside the surf. Beyond the surf youcan inflate your BCD and switch to your snorkel to swim out toyour dive site.

Exits. When you’re ready to leave the water through surf, stopoutside the surf zone and watch the waves. Again, watch the wavesets — where they’re breaking and when. The pattern can changeduring your dive, so take the time to check. Evaluate the situationand discuss it with your buddy.

Always save some air for exiting, because you’ll use your regulatoras you pass through the surf. Wait until the surf pattern reaches alull, then swim toward shore as quickly as possible, keeping ahand on your mask when waves hit and checking your buddyevery few seconds. Swim steadily with a free hand extended aheadof you. Avoid stopping in the surf zone and swim until you’re inshallow water. If the backrush is strong and you are tired, youmay elect to swim up to the beach and crawl out on your handsand knees. If you stumble in the waves, don’t try to get up — justcrawl out.

Handle waves the same way you did while entering — by stop-ping, holding your mask firmly and leaning against it. When youstand up, walk backward so you can watch the waves and stay

Chapter Three 173

Hurry through the surf.Breathe from your regulatorwhen entering through surf.Your buddy should be nextto you, and if you’re towing afloat, it should be betweenyou and the shore so a wavecan’t push it into you. Theidea is to get through thesurf zone as quickly aspossible.

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beside your buddy. If you have a surface float, push it ahead ofyou so it stays between you and the shore.

Surface SwimmingSwimming on the surface in open water dif-fers from surface swimming in confinedwater. You may have lower visibility, youmay have longer distances to swim, andthere may be currents or waves. You’vebeen simulating the right habits duringyour confined water dives, but here are afew reminders:

1. Swim with your BCD about half full so you won’t have tostruggle to stay at the surface. Don’t over inflate your BCD,though because it creates unnecessary drag.

2. Pace yourself. Swim at a steady, comfortable pace. Surfaceswimming tires you more than swimming underwater, so don’ttry to go as fast.

3. Streamline yourself as much as possible. Keep your arms atyour sides.

4. Use your snorkel, breathing cautiously to avoid choking onwater that may enter the snorkel due to small waves.

5. Keep your fins below the surface when kicking. You may wishto swim on your side or back if conditions allow.

6. Check your location, direction and your buddy every 30 sec-onds or so. Stay close to your buddy, maintaining physical con-tact if necessary. Use something on shore, or an anchored boat,for orientation.

Descents in Open WaterYou’ve been practicing proper descents during your confinedwater dives, but there are some points to remember in openwater due to the greater depths and the bottom composition.

If you’re weighted properly, you should be able to descend byslowly deflating your BCD and exhaling. Make the entire descentwith your head above your feet, so you maintain control and ori-entation, and keep contact with your buddy. Remember to equal-ize your air spaces early and often during the descent.

You want to maintain neutral buoyancy during the descent —don’t wait until you reach the bottom. Add small amounts of air


Use your snorkel.Swimming on the surface inopen water differs fromsurface swimming inconfined water. You mayhave lower visibility, youmay have longer distancesto swim, and there may becurrents or waves.

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Chapter Three 175

as you descend so you reach the bottom neutrally buoyant. Thisminimizes kicking and stirring up the bottom.

For control and reference, it’s a good practice to use a line duringdescents, or follow the bottom contour. If you descend along theanchor line of a boat, hold the line at arm’s length so it won’tstrike you as the boat pitches up and down in the waves. Let yourarm swing up and down with the line like a shock absorber so itdoesn’t jerk you up and down.

You want to descend steadily and with minimal effort, while main-taining neutral buoyancy so you can stop your descent at anytime. Maintain buddy contact and stay oriented so you have yoursense of direction when you reach the bottom.

Here’s a preview of the skills and procedures you’ll practice dur-ing your first two Open Water Dives. The sequence within eachdive will vary, depending on the logistics, and your instructor maysequence some skills in different dives. Before each dive, yourinstructor will brief you about what you’re going to do and when,along with other information you need for the dive, like communi-cation signals, an environmental orientation, emergency proce-dures, safety rules, and so on.

Open Water Dives 1 and 2

Equalize early and often.As you descend, maintainbuddy contact and stayoriented so you have yoursense of direction when youreach the bottom.

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Open Water Dive 1 introduces you to theskills you’ll use on virtually all dives, tothe experience of exploring underwater,and to the differences between confinedwater and open water. Open Water Dive 2expands on this, plus you’ll practice someof the skills you’ve mastered during theconfined water dives.

Open Water Dive 1OverviewBriefingEquipment preparationDon and adjust equipmentPredive safety checkEntryBuoyancy/weight checkControlled descent (max 12 m/40 ft)Underwater explorationAscentExitDebrief and log dive


Open Water Dive 2OverviewBriefingEquipment preparationDon and adjust equipmentPredive safety checkEntryBuoyancy/weight check(Cramp removal self and buddy)*(25 metre/yard tired diver tow)*(Snorkel/regulator exchange)*Controlled descent (max. 12 m/40 ft)Buoyancy control — fin pivot, low pressure

inflatorPartial and complete mask flood and clearRegulator recovery and clearingAlternate air source use stationary and AAS

assisted ascentUnderwater exploration and buoyancy controlAscent(Weight removal at the surface)*ExitDebrief and log dive

* These skills may be sequenced inother dives, depending on logistics.

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Knowledge Review—Chapter 3

Knowledge Review—1. There are several factors that affect visibility underwater. Check those listed here.

a. weatherb. water movementc. ambient pressured. suspended particles

2. True or False: To avoid problems associated with diving in clear water, use an accu-rate depth gauge, refer to it frequently and it is recommend that you use a line forascents and descents. ____________

3. Explain what you should do if you find yourself caught in a current at the surface.

4. True or False: You will find it easier to swim against a mild current along the bottomwhere it is generally weaker than on the surface. ____________

5. Check one. If a current is present, you should generally begin your dive:

a. with the current.b. across the current.c. against the current.

6. Check one. Nearly all injuries from aquatic life are caused by_________action on thepart of the animal.

a. unpredictableb. unprovokedc. defensive

7. Describe what you should do if you spot an aggressive animal underwater.

8. True or False: For safety and enjoyment when diving in a new area or engaging in anew activity, be sure to obtain a proper orientation. ____________

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9. A rip current can be recognized as a line of turbid, foamy water moving:

a. toward shore.b. seaward.c. parallel to shore.

10. Outline three ways to prevent or control most diving problems that occur at the surface.

1.__________________________________________________________________________

2.__________________________________________________________________________

3.__________________________________________________________________________

11. True or False: The first step in assisting another diver with a problem at the surfaceis to talk to him, offering encouragement and persuading him to relax. ____________

12. Arrange the five low-on-air/out-of-air emergency procedures in order of priority from1 through 5.

Buoyant emergency ascentControlled emergency swimming ascentNormal ascentBuddy breathing ascentAlternate air source ascent

13. Check one. If you become entangled underwater, you should:

a. Twist and turn to free yourself.b. Stop, think and then work slowly and calmly to free yourself.

14. True or False: With an unconscious diver, the primary concern is to remove him fromthe water. ________________

15. True or False: Once removed from the water, an unconscious breathing diver shouldbe administered oxygen if available.

Student Diver Statement: I’ve completed this Knowledge Review to the best of my ability,and any questions I answered incorrectly or incompletely I’ve had explained to me, and Iunderstand what I missed.

Name ________________________________________________ Date ________________________

Knowledge Reviews may not be reproduced in any form without the written permission of the publisher.

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PADI Open Water Diver Manual_03

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