Supplementary Guidance for Reporting Hydrocarbon … Guidance for Reporting Hydrocarbon Releases UK...

Supplementary Guidance for Reporting Hydrocarbon Releases

UK Offshore Operators Association


September 2002

September 2002 Produced in Cooperationwith the HSE

1


SUPPLEMENTARY GUIDANCE FOR REPORTING OF HYDROCARBON RELEASES This document is supplementary to the existing guidance on reporting of offshore hydrocarbon releases (OTO 96 956), and should be used in conjunction with that document when completing and submitting OIR/12 reports. 1. SUMMARY A flowchart has been produced to aid decision making on the reporting of hydrocarbon releases, and this is enclosed as Appendix A. As a brief guide :

o ALL offshore ignitions (i.e. fires, explosions) are reportable no matter how small. In these cases, the RIDDOR definitions are clear and unambiguous. There is no need to consider potential or emergency actions, if it ignites, report it!

o All 2-phase and condensate releases should be considered as reportable. o For all other releases to be reportable under RIDDOR (DO 73), unless they

actually ignite (see above), then the potential for ignition/escalation needs to be examined, particularly in the case of releases in the minor range.

o The extent of actions taken to prevent or limit the release are taken as an indication of the potential for escalation (see existing RIDDOR guidance and OTO 96 956 where examples of such actions are given e.g. alarms, shutdowns, withdrawal of permits, withdrawal of personnel from the area, musters, etc.) If any of these actions take place, then the release is deemed reportable.

o For Subsea Wells, hydrocarbon releases from these are reportable as well incidents (DO 13). However, only those involving an installation (e.g. MODU or “parent platform”) and controlled from there will need an OIR/12.

o For Subsea Pipeline releases (DO 14), only those occurring within the 500 metres safety zone of an installation will need an OIR/12.

2. SUBMISSION OF OIR/12 FORMS

Completed OIR/12 forms should now be submitted to the Health & Safety Executive, HID Central Intelligence Unit, Data Management Section (CD4C), at the following address:

2nd floor St Anne's House University Road BOOTLE Merseyside L20 3RA Or by e-mail to: [email protected]

NB : • OIR/12 documentation should NOT be submitted to the Incident Contact Centre,

which only deals with incident reporting (i.e.OIR/9b) under the RIDDOR regulations. • OIR/12 forms should NOT be submitted to any HSE address other than the above,

i.e. they must be sent separately from the OIR/9b. • Interactive forms, which may be completed on-line and e-mailed direct to HSE

(including OIR/9b and OIR/12) will shortly be available from the HSE web-site (http://www.hse.gov.uk). In addition, the HCR System is being upgraded to allow submission of OIR/12 forms direct into the HCR system database via the internet. Planned to be on-line in early 2003.

September 2002 2


3. LINK BETWEEN OIR/12 FORM AND PARENT OIR/9B SUBMISSION

• OIR/12 forms can only be entered and checked in the Hydrocarbon Releases Database when parent OIR/9B information has been submitted under RIDDOR to HSE via the Incident Contact Centre.

• If the release is not reportable under RIDDOR (see also section 1. ‘REPORTABILITY’ above), then an OIR/12 form is not required either, and should not be submitted because it cannot be processed separately.

• All process and non-process hydrocarbon releases reportable under RIDDOR must be reported under Dangerous Occurrence(DO)Code 73 (Release of Petroleum Hydrocarbon).

• Hydrocarbon fuelled fires and explosions are ALL reportable under RIDDOR, irrespective of the size of fire, time of burning or damage caused. These must also be reported under DO Code 73 (Release of Petroleum Hydrocarbon) and NOT under DO Code 74 (Fire or Explosion), which is for fires and explosions other than those fuelled by petroleum hydrocarbon.

• Hydrocarbon releases from Wells and Pipelines, however, may still be reported under DO 13 and DO 14 respectively to bring these to the direct attention of wells and pipeline specialists respectively.

4. OFFSHORE INSTALLATION DETAILS AND LOCATION OF INCIDENT Name (or other designation) The name of the installation should specify the platform (or MODU) on which the hydrocarbon release occurred (e.g. Bruce CR, Marnock PUQ) rather than more general designations such as Bruce Complex, ETAP, well number, etc. Registration Number The use of Registration Numbers was discontinued following the introduction of the Management and Administration Regulations (MAR) in 1995, and thus these no longer need to be reported on the OIR/12 form. Location • Full location details (Quadrant, Block, Latitude and Longitude) are required on the OIR/12

form, especially for incidents involving mobile installations. • It is insufficient to state only the name of the field involved. • Quadrant and Block numbers should be inserted in the separate fields designated for this

information e.g. Quadrant 9; Block 13c. Please DO NOT show them in one field e.g. in the form 9/13c

5. MAIN OIR/12 FORM COMPLETION

Hydrocarbon Released

• Releases of unprocessed hydrocarbon fluids (from wells, flowlines, manifolds and drilling/workover operations) should be coded as 2-phase.

• Releases downstream of separation (such as oil/gas/produced water releases, for example) should be coded as the hydrocarbon type related to the parent stream i.e. gas, oil, or condensate, not as 2-phase.

• Releases of non-process hydrocarbons such as diesel, helifuel, lub oil, hydraulic oil, seal oil, glycol, methanol, oil-based mud etc. are also reportable under RIDDOR, and an OIR/12 is also required for these.

• Any gas density quoted should be at operating (i.e working) conditions, rather than a relative density.

• Please remember to give gas density, liquid gravity, and GOR for 2-phase releases.

September 2002 3


Parameters for Basic Severity Classification

• To classify the basic severity (i.e. major, significant, minor) it is important that the best possible estimates of “estimated quantity released”, “equivalent hole diameter”, “duration”, and “actual (working) pressure” are provided.

• It is extremely difficult to estimate the severity if two or more of these parameters are not provided , or are quoted as “not known”, "too small to measure" or "impossible to quantify”.

• Advisory tables which can aid the estimation of these basic parameters are enclosed in Appendix A. However, it is recommended that a process engineer be consulted on this aspect prior to submission of the OIR/12 form.

• The “equivalent hole diameter” should be the hydraulic equivalent (round) hole diameter which, if it is not round (e.g. crack, split ) may be calculated from the actual hole geometry as 4A/P, where A = cross-sectional area, and P= Wetted Perimeter.

Location of Leak

Module / Area Name This field is often used to determine (or corroborate) the system from which the hydrocarbon release emanated. It would therefore be helpful to avoid using company or plant specific terminology, or very general area designations here, (e.g. Module A, PO4, Level 1, Package 4, Main Deck, Process Area) but to identify actual plant names instead e.g. Separation module, wellheads module, etc. System Selection

• It is essential that a single system is selected from the list on the OIR/12 form for

any one hydrocarbon incident. • The series of tick boxes and other boxes for completion/deletion are based on the

definitions quoted in OTO96 956, and the choices made should best describe the system considered to be responsible for the release.

• Avoid situations where all topsides incidents are coded solely as the "Processing" system, for example.

• A number of hydrocarbon releases are "carry-over" type incidents, where a hydrocarbon release occurs and the material passes through other systems / equipment before subsequently being released to atmosphere. (e.g.via the flare system).

• Where possible, the system (and equipment) selection should represent the items from which the hydrocarbon emerged (e.g. piping within the flare system).

• In “carry over” incidents, the causation details (see below) may then be used to reflect the mode of failure of the system and/or equipment item which caused the release.

• System Selection Hints:

o Incidents involving Drilling Operations should be coded as "Drilling" from the system list. They must also be further described as either Exploration or Appraisal or Development or Completion, by selecting the appropriate parameter from this section of the OIR/12 form. The selection should also show whether the operation was on an Oil or Gas well, and one of the water depth ranges (viz: <100m, 100-700m, 701-1000 metres, >1000 metres) should also be selected.

o Incidents involving Well Operations (i.e. wireline, workovers) should also be coded as "Drilling" from the system list. They must also be further described as either Wireline or Coiled Tubing or Snubbing or Well Test or Recompletion or Abandonment (or Other if necessary), by adding this to the OIR/12 form. The selection should also show whether the operation concerned was on an Oil or Gas well, and whether the operation was With Tree or Without Tree.

September 2002 4


o Incidents involving permanent drilling equipment should also be coded as "Drilling" from the systems list, but no further system related information is required in this instance. The equipment type should then be specified using only the Mud / Shale / Drilling option on the OIR/12 equipment list (see below).

o “Well Control” system should be selected for BOP equipment releases. o “Well” system should be selected for Wellhead or Xmas Tree equipment

releases. The type of well should then be indicated from oil production or gas production or gas injection, and whether surface or subsea.

o “Processing” systems should be either oil or gas. See OTO 96 956 for secondary choices.

o “Utilities” systems should be either oil or gas. See OTO 96 956 for secondary choices.

o “Flowlines Other” includes choke and kill lines. o “Manifolds Other” includes choke and kill manifolds. o Incidents involving a fuel line to a turbine should be coded as either the

“Diesel” or “Fuel Gas” system, rather than the “Power Generation” system.

Equipment Selection

• It is essential that a single item of equipment is selected from the list on the OIR/12

form for any one hydrocarbon incident. • The series of tick boxes and other boxes for completion/deletion are based on the

definitions quoted in OTO96 956, and the choices made should best describe the equipment item considered to be responsible for the release.

• Equipment selection hints :

o No equipment type need be selected for Drilling Operations, since the equipment population in the database excludes downhole components.

o No equipment classification is required to be selected for Well Operations (or workover) as these are characterised by the use of temporary equipment, which is not a permanent part of the installation.

o For a permanent drilling system failure (i.e. not Drilling/Well Operations) the equipment type should then be specified using only the Mud / Shale / Drilling option.

o “Well Control” system incidents should only ever be related to BOP equipment (and not component flanges / valves etc.).

o “Well” system incidents should only ever be related to Wellhead or Xmas Tree equipment (and not component flanges / valves etc.)

o Incidents involving a fuel line to a turbine should be coded as either the “Diesel” or “Fuel Gas” system, rather than the “Power Generation” system.

o Topsides flowline incidents should be associated with piping, rather than pipelines.

o It is important to distinguish between major equipment items such as compressors / turbines / pumps, and the piping connected to them. Only select the major equipment if the release was from the actual vessel, pump or compressor, otherwise choose the actual flange, piping or valve as the piece of equipment involved.

o It is important to source and report precise equipment details, since it can be very difficult to estimate these with any accuracy if not given on the form, namely :

For Pig Traps and Pressure Vessels: Indicate whether horizontal or vertical, plus give length and diameter

For Storage Tank : Give capacity (m3) For Compressors and Pumps : Indicate whether centrifugal or

reciprocating and whether single or double seal

September 2002 5


For Heat Exchangers : Indicate whether Plate or Hydrocarbon in Shell or Hydrocarbon in Tube.

For Valves: Indicate whether Manual or Actuated, plus give Function (e.g. control, block, etc.) plus Type (e.g. gate, ball, globe, etc.) plus Size.

For Flanges, Piping, Pipelines and Risers the rating should be expressed in psig or barg (not in ANSI, API etc.)

For Piping, Pipelines and Risers the material type should be either Steel or Flexible (no need to give specification).

Hazardous Area Classification

• Zone 1: An area in which hydrocarbons, in the form of an explosive vapour/air

mixture, is likely to occur in normal operation (drill floor, vent or flare area). • Zone 2: An area in which hydrocarbons are not likely to occur in normal operation,

and if occurring will exist only for a short time (process, wellhead area). • Unclassified: Non-hazardous area (e.g. accommodation).

Total HC Inventory in System The calibre of information quoted in this field is variable, and sometimes difficult to relate to the estimated quantity released. Since we need to be able to relate estimated quantity released to the total HC inventory, in terms of estimated percentage inventory lost, the units used here should preferably be the same as those used in estimated quantity released. Also, the inventory should be the amount normally resident in the system e.g. held between isolation valves at the defined limits of the system. Extent of Dispersion As well as giving details of how hydrocarbons accumulated or dispersed in the area i.e. extent of liquid pool or gas cloud, this box may also be used to describe details of gas detection (in terms of LEL etc.) together with details of why fixed gas detection failed to detect a particular leak. Cause of Leak For any one hydrocarbon incident, it is essential that a single factor is selected from each category (i.e. design, equipment, operational and procedural causation) on the OIR/12 form.

• Design : Choose either “related to design” or “no design failure”. • Equipment: Choose either “No failure in the equipment itself” or

o Corrosion which should be further specified as either Internal or External.

o Mechanical which should be further specified as either Failure or Fatigue or Wearout.

o Erosion o Material defects o Other equipment failure which should be further explained in text.

• Operation : Choose either “no operational failure” or o Incorrectly fitted o Improper which should be further specified as either Maintenance or

Inspection or Testing or Operation. o Dropped Object / Other Impact which should be further specified as

either Dropped Object or Other Impact. o Left open o Opened when containing Hydrocarbon o Other operational failure which should be further explained in text.

• Procedural: Choose either “no procedural failure” or

September 2002 6


o Noncompliance with, which should be further specified as either Procedure or Permit to Work.

o Deficient Procedure o Other procedural failure which should be further explained in text.

• NB : The "Other" Equipment, Operational and Procedural causation categories should

not be used to code statements that relate to existing code choices. For example : • "suspect mechanical failure" should have been coded as Mechanical Failure • "potential corrosion/erosion" should have been coded as either Erosion or Internal /

External Corrosion • "operator left valve open" should have been coded as Left Open, etc. Operational Mode (in the area at the time of release)

• Operational Mode should be used to confirm the status of work ongoing IN THE AREA

OF THE RELEASE. This means that if some maintenance, construction, pigging, workover, sampling, equipment start-up, or other operation was being carried out on or around the equipment when it leaked, then that box should be ticked, even if the remainder of the Installation was in normal production. For the remaining Operational Mode selections, further factors should be specified during selection, viz:

• Drilling or Well Operations: the choice here should match the system selection (see

section on “System Selection” above) • Normal Production: Use this only where everything was normal with no intervention going

on in the area. • Pigging • Shutting Down / Shutdown / Blowdown should be further specified as either Shutting

Down or Shutdown or Blowdown. • Flushing / Cleaning / Inspection should be further specified as either Flushing or

Cleaning or Inspection. • Maintenance should be further specified as either Hot Work or Other, with further text to

explain • Construction should be further specified as either Hot Work or Other, with further text to

explain • Testing / Sampling should be further specified as either Testing or Sampling. • Reinstatement / Start-up should be further specified as either Reinstatement or Start-up.

o Reinstatement should be used where the system was re-started following work carried out on the item or plant from which the release emanated including maintenance / construction operations, inspection, testing, venting etc. including planned shutdowns.

o Start-up should be used where the system was re-started following an operational shutdown such as a plant trip etc, and where no intervention work was carried out.

o If the Reinstatement / Start-up is known to have followed a shutdown but it is not clear whether this was following maintenance or construction etc., then REINSTATEMENT should be assumed.

o If it is not known whether the Reinstatement / Start-up followed a shutdown or not, then START-UP should be assumed.

Ignition Source and Ignition sequence • Ignition Source information is invaluable in the modelling of ignitions, and for analysing

ignition probabilities. Details of the ignition source(s) must therefore be given (e.g. hot work in area, spark from electrical contact, hot exhaust, spark from metallic impact etc.) especially as this information is published in the annual hydrocarbon statistics report for each ignition reported.

September 2002 7


• The ignition sequence is also important in ignitions modelling, and so the order of events should be indicated by entering the sequence number(s) in the box(es) shown. For example, for a Flash fire followed by an Explosion put ‘1’ in Flash Fire and ‘2’ in Explosion.

• Also indicate whether the ignition was immediate or delayed by ticking the appropriate box. If delayed, the time of delay should also be added in seconds.

Emergency Actions Shutdown and Blowdown emergency action codes do not solely relate to the shutdown and/or blowdown of an entire system, but may also be used to describe instances of shutdown/blowdown of individual items of machinery and sections of process, rather than describing these in the "other emergency actions" field (though isolation activities can be coded as "other emergency actions"). Additional Comments This field is intended for use as an area where any other relevant information on the incident may be added, other than that already provided in the various sections relating to weather, extent of dispersion or other emergency actions. For example, details of injuries or damage caused, results of investigations etc. may be added here.

September 2002 8


September 2002 9

Is it an intentionalRelease ?

Is it a HydrocarbonRelease?

Does it meetreportable criteria ?

Was emergencyaction required to

prevent escalation ?

Did ignition occur ?

Submit OIR 9bwithin 10 days of

Incident Occurring

Investigate

Estimate Mass ofRelease and otherreportable criteria

ConsultOnshoreProcessEngineer

Useadvisorytables asrequired.

Submit OIR 12within 30 days of

Incident Occurring

Are other reportsrequired ?

Internal companyrecord

PON 1 forEnvironmental

Spill

Yes

Yes

Yes

Yes

No

No

No

No

Yes

No

Guidance Notes

Any unintentional release within 500m zone, which results in;- a fire or explosion- the taking of action to prevent or limit the consequences of apotential fire or explosion- has the potential to cause death or major injury to any person.

GAS / 2-Phase: A release is reportable if it is;1. A CONTINUOUS release at a rate greater than 1 kg / hour,Nominally 20% LEL at 0.1 metresOR2. A DISCRETE release with a total mass of greater than 0.1 kg

LIQUIDS : A release is reportable if it is ;1. A CONTINUOUS release of 100% hydrocarbons at a rategreater than 5 kg/ day ( approx 4 drips / minute ), nominally 0.25litres / hour.2. A DISCRETE release of 100% hydrocarbon, of greater than5kg, ( nominally 5 litres ).3. If produced water, the oil content must be greater than 10%,and the total mass OF HYDROCARBONS released is greaterthan 5kg, ( nominally 5 litres ).

Typical Substances;Gas, Oil, Condensate, 2-Phase, and Non-process

( Diesel, fuel oil, glycol, helifuel, lub-oil, methanol, heat transfer oil,hydraulic oil, seal oil, bottled gas etc.)

Intentional Releases are defined as;

- Routine releases such as flaring, venting, sampling etc.

where the activity remained within controlled limits and nomitigating actions were required to prevent escalation

Emergency stoppage of plant, either automatically or by operator,to control the leakage of process or non-process hydrocarbons.Stoppage of, or suspension of work on a particular process, orstoppage of a permit to work following the confirmation of ahydrocarbon release with a potential for fire or explosion.Operation of a deluge, fixed fire-fighting system, blow-down etcGeneral shutdown, muster, evacuation of an area, or andcombination of these following a confirmed release.

End

No

Yes

Are other reportsrequired ?

No

Yes

RaiseReportsas required

Note 1

Note 1

Note 2

Note 3

Note 4

Note 4

Note 3

Note 2

OIR/9b for otherRIDDOR eventse.g. HP water,

mud, H2S

Did itescalate ?

No

Yes

Appendix A. A Flowchart Summary of the Reporting Guidelines


APPENDIX B: Estimation of Gas Volumes Released

The following graphs and tables help give guidance on estimating the mass of gas released for different, leak hole sizes, pressures, pipe system inventories etc.

Small Continuous Release Flowrates

0.00001

0.0001

0.001

0.01

0.1

1

10

100

1000

1 10 100 1000

Pressure (bara)

Mas

s Fl

owra

te (k

g/m

in)

10mm

5mm

3mm

1mm

0.5mm

0.1mm

Graph showing mass flow rates in kg/minute for a Small Continuous Gas Release

Pressure ( Bara )

Nominal Pipe Diameter ( inch )

3” 4” 6” 8” 10” 11” 12” 1 0.0045 0.0079 0.0178 0.0317 0.0495 0.0599 0.0713 5 0.0223 0.0396 0.0891 0.1585 0.2476 0.2996 0.3565

10 0.0446 0.0792 0.1783 0.3169 0.4952 0.5992 0.7131 15 0.0699 0.1188 0.2674 0.4754 0.7428 0.8988 1.0696 20 0.0891 0.1585 0.3565 0.6338 0.9904 1.1984 1.4261 25 0.1114 0.1981 0.4457 0.7923 1.2380 1.4979 1.7827 50 0.2228 0.3962 0.8913 1.5846 2.4759 2.9959 3.5654

100 0.4457 0.7923 1.7827 3.1692 4.9519 5.9918 7.1307 150 0.6685 1.1885 2.6740 4.7538 7.4278 8.9877 10.6961 200 0.8913 1.5846 3.5654 6.3384 9.9038 11.9836 14.2614 250 1.1142 1.9808 4.4567 7.9230 12.3797 14.9795 17.8268

Table showing Mass of Gas per Meter Length of Piping ( kg/m )

September 2002 10


Estimation of Gas Volumes Released.- When Blowdown has been Initiated

The following graphs provide guidance/help in an initial estimate of the TOTAL mass of Gas released, assuming that the ESD/Blowdown commenced at the time of the initial release and operated during the entire period. Calculations have been performed for various system volumes from 10 m3 to 500m3. Assumptions; Gas Molecular weight = 26 kg/k-mole Blowdown rate = As per API 521 ( Blowdown from operating pressure to either half the original or 8 bara , which ever is the lowest, within 15 minutes of blowdown operation )

Mass of Gas Released From a 1mm Dia. Hole (Following ESD/Blowdown)

0.1

1

10

2 5 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200

System Operating Pressure (bar)

Mas

s R

elea

sed

(kg)

10m3 25m3 50m3 100m3 200m3 500m3

Mass of Gas Released From a 3mm Dia. Hole (Following ES D/Blowdown)

1

10

100

2 5 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200

Syste m Ope rat ing Pre ssure (bar)

Mas

s R

elea

sed

(kg)

10m3 25m3 50m3 100m3 200m3 500m3

September 2002 11


September 2002 12

Mass of Gas Released From a 5mm Dia. Hole (Following ESD/Blowdown)

1

10

100

1000

2 5 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200

System Operating Pressure (bar)

Mas

s R

elea

sed

(kg)

10m3 25m3 50m3 100m3 200m3 500m3

Supplementary Guidance for Reporting Hydrocarbon … Guidance for Reporting Hydrocarbon Releases UK...

Documents

Transcript of Supplementary Guidance for Reporting Hydrocarbon … Guidance for Reporting Hydrocarbon Releases UK...