Ionising Radiation Safety Procedure

BSP-02-Standard-1631

HSE STANDARD MODULE 20 IONISING RADIATION SAFETY

THIS

IS A SUPPORTING DOCUMENT FOR THE EXECUTING ACTIVITIES IDENTIFIED IN BSP-12 & BSP-72, AND SIMILAR ACTIVITIES IN ALL BRUNEI SHELL JOINT VENTURE COMPANIES

Revision 4a

Approved: Document Owner:

Lee Wai Chee, HSE Pg. Noralim Pg. Hj. Ahmad, SEN/1

BSP – Ionising Radiation Safety

Module 20

Document Control DOCUMENT TYPE DOCUMENT OWNER Standard SEN/1 DOCUMENT REFERENCE AUTHOR TMS1631 HSE/41 KEY WORDS Ionisation, Radiactive, safety, source, register

SECURITY CLASSIFICATION Unclassified APPROVED BY HSE

Revision Record REV 1.0 2.0 3.0

4.0

REVISION DESCRIPTION

DATE

st

1 Issue 2nd Issue rd 3 Issue – converted to MS-Word from Pagemaker; removed references to asset holders, RA Committee; converted to TMS format; inserted references to Brunei legislation 4th Issue – Approval and Ownership changes 4.10 clause (n) BLNG – source strength limit included.

March 1999 July 2001

January 2006

Distribution Control Distribution of this document is controlled by the Document Owner. The document is located on the BSP Intranet >Homepage>Corporate>HSE Website>HSE Documentation

Notice and Warning Copyright 2001, Brunei Shell Petroleum Company Sendirian Berhad This document is the property of Brunei Shell Petroleum Sendirian Berhad (BSP), KB3534, Negara Brunei Darussalam. Circulation is restricted to BSP and its designated associates, contractors and consultants. It must not be copied or used for any other purpose other than which it is supplied, without the expressed written authority of BSP. Except where provided for purposes of contractual requirements, BSP disclaims any responsibility or liability for any use or misuse of the document by any person and makes no warranty as to the accuracy or suitability of the information to any third party. Any misuse of the document is repressible by BSP.

Ionising Radiation Safety - Rev 4a

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Module 20

Contents 1

INTRODUCTION ......................................................................................................................................... 5

2

ORGANISATION AND RESPONSIBILITIES.......................................................................................... 6 2.1 THE BRUNEI SHELL JV COMPANIES INDEPENDENT RADIATION PROTECTION OFFICER (IRPO) ................ 6 2.2 ROLES AND THEIR RESPONSIBILITIES ........................................................................................................ 6 2.2.1 Radiation Protection Officer (RPO) .................................................................................................. 6 2.2.2 Radiation Focal Point (RFP)............................................................................................................. 6 2.2.3 Radiation Protection Supervisor (RPS)............................................................................................. 7 2.2.4 Medical Officer.................................................................................................................................. 7 2.2.5 Contract Holder................................................................................................................................. 7 2.2.6 Asset Holder ...................................................................................................................................... 8 2.2.7 Contractor ......................................................................................................................................... 8

3

LOCAL RULES............................................................................................................................................. 9

4

RADIOLOGICAL OPERATION .............................................................................................................. 10 4.1 PERSONNEL ............................................................................................................................................. 10 4.2 CONTRACTOR .......................................................................................................................................... 10 4.3 CLASSIFIED WORKERS ............................................................................................................................ 10 4.3.1 Industrial Radiographic Team......................................................................................................... 12 4.4 EQUIPMENT ............................................................................................................................................. 12 4.5 SAFETY EQUIPMENT ................................................................................................................................ 12 4.5.1 Portable Survey Meter..................................................................................................................... 12 4.5.2 Audible Alarms (Bleepers)............................................................................................................... 12 4.5.3 Thermoluminescent Dosemeter (TLD)............................................................................................. 12 4.5.4 Film Badge ...................................................................................................................................... 13 4.6 LOW SPECIFIC ACTIVITY (LSA) RADIOACTIVE SCALE ............................................................................ 13 4.7 SAFE DISTANCE ....................................................................................................................................... 13 4.8 SHIELDING ............................................................................................................................................... 13 4.9 EXPOSURE TIME ...................................................................................................................................... 13 4.10 WORKING WITH IONISING RADIATION SOURCES .................................................................................. 14 1.11 CHANGE OF RADIOACTIVE ISOTOPES ................................................................................................... 16 1.12 DOSE LIMITS ........................................................................................................................................ 16 1.13 RECOMMENDED TARGET ..................................................................................................................... 16 1.14 DOSE LIMITS FOR MEMBERS OF THE PUBLIC ....................................................................................... 16

5

REGISTERS AND RECORDS................................................................................................................... 17 5.1 REGISTER OF CLASSIFIED WORKERS ....................................................................................................... 17 5.2 PERSONAL RADIATION DOSE RECORDS ................................................................................................... 17 5.3 RADIOACTIVE SOURCE REGISTER ............................................................................................................ 17 REGISTER OF X-RAY EQUIPMENT ....................................................................................................................... 19 5.5 LEAK TESTING AND INSPECTION RECORDS ............................................................................................. 19 5.6 PURCHASING RECORDS ........................................................................................................................... 20 5.7 RADIOACTIVE SUBSTANCE TRANSFER..................................................................................................... 20 RECORDS OF DISPOSAL ...................................................................................................................................... 21

6

STORAGE.................................................................................................................................................... 23 6.1 6.2

7

TRANSPORTATION.................................................................................................................................. 25 7.1 7.2 1.3 1.4 1.5 1.6 1.7 1.8

8

STORAGE OFFSHORE ............................................................................................................................... 23 STORAGE ONSHORE ................................................................................................................................. 23 GENERAL REQUIREMENTS ....................................................................................................................... 25 LABELLING .............................................................................................................................................. 25 PACKAGING ............................................................................................................................................. 26 CONSIGNMENT CERTIFICATES ................................................................................................................. 26 TRANSPORT BY AIR ................................................................................................................................. 27 TRANSPORT BY SEA ................................................................................................................................. 27 TRANSPORT BY ROAD.............................................................................................................................. 27 TRANSPORTATION INCIDENTS ................................................................................................................. 28

REFERENCES............................................................................................................................................. 30


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8.1 8.2 8.3 8.4 8.5

Module 20

BRUNEI DARUSSALAM LEGISLATION ...................................................................................................... 30 UNITED KINGDOM LEGISLATION, REGULATION, ETC. ............................................................................. 30 INTERNATIONAL REFERENCES ................................................................................................................. 30 SIEP........................................................................................................................................................ 30 BRUNEI SHELL JV COMPANIES....................................................................................................... 30

APPENDIX A - GLOSSARY OF TERMS ....................................................................................................... 31 APPENDIX B - RADIOACTIVE SUBSTANCE INCIDENT CHECKLIST ................................................ 33 APPENDIX C - RADIATION PROTECTION GUIDELINES ...................................................................... 34 APPENDIX D - IONISING RADIATION EMERGENCY PROCEDURE .................................................. 36 APPENDIX E - IONISING RADIATION SAFETY REVIEWS.................................................................... 40 APPENDIX F - RADIOACTIVE SUBSTANCES INFORMATION ............................................................ 42


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1

Module 20

INTRODUCTION Radioactive substances are in common use in the oil and gas industry and although there are known hazards associated with them, experience has shown that with proper controls applied, they can be used safely without risk to health, or the environment. Two sources of ionising radiation are encountered in BRUNEI SHELL JV COMPANIES activities, with a third which exists in only insignificant quantities but could increase in the future. •

The first source is radioactive substances, either sealed or unsealed.

•

The second source is X-ray machines.

•

The third source is naturally occurring, low specific activity (LSA) radioactive substances.

These sources emit ionising radiations capable of inducing three categories of biological effect which are injuries, long term risks and genetic; these are further described below. The injuries or acute effects appear in the weeks immediately following exposure to a high dose of radiation. Usually, injuries are localised in relatively small areas and appear as deep burns. The effects may also be more general and result in nausea, vomiting and an overall feeling of being unwell. The severity is proportional to the dose received and in extreme cases can prove fatal. The long term risks or chronic effects are less obvious. There is some evidence that if high doses are received to the whole body, exposure may slightly increase the likelihood of cancer being developed. All the known data on genetic effects has been largely obtained from animal experiments. There is no data which associates any genetic effects with the normal exposures to be anticipated in the industrial uses of radioactive substances. The purpose of this standard is to clearly specify the levels of safety required for work involving ionising radiation. Compliance with this standard will ensure that: •

work is properly controlled.

•

safeguards are in place to protect the health of people carrying out work with ionising radiations.

•

safeguards are in place to protect the health of other people and the general public.

•

proper records are kept and maintained.

•

radioactive materials are stored, transported and disposed of properly.

Special Note In addition to the legislation of Brunei Darussalam for radiation matters, BRUNEI SHELL JV COMPANIES has adopted the International and United Kingdom legislation listed towards the end of this document (see Section 8 - References).


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2

ORGANISATION

2.1

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AND

RESPONSIBILITIES

The Brunei Shell JV Companies Independent Radiation Protection Officer (IRPO) In accordance with the Shell Safety Committee “Ionising Radiation Safety Guide” November 1993, Section 2.5.1, Brunei Shell JV Companies will appoint an Independent Radiation Protection Officer (IRPO), in preference to having a committee. The function of the IRPA is to advise BRUNEI SHELL JV COMPANIES management on all matters regarding the supervision and control of work with ionising radiation. With the approval of BRUNEI SHELL JV COMPANIES management, the IRPO can also allocate specific duties and appointments to its individual members or other authorised personnel.

2.2

Roles and their Responsibilities

2.2.1

Radiation Protection Officer (RPO) Qualification and Experience shall be as per BSP Standard 12-P-10. Contractors carrying out works with ionising radiation shall appoint one or more RPO’s for the purposes of advising them of the observance of these and other legislative regulations in connection with ionising radiation. The person appointed as RPO to BRUNEI SHELL JV COMPANIES shall normally be sourced from an independent body, consultancy or organisation which specialises in providing this type of advisory service. The appointment may not necessarily be a full-time one, but one which is available on an as-and when required basis. An RPO shall be familiar with the requirements laid down in this document and in the Shell Safety Committee "Ionising Radiation Safety Guide", and in addition to meeting the requirements of the Ionising Radiations Regulations 1985, shall: •

Be registered with the DSS, Ministry of Health and possess a valid Industrial Radiation Worker Registeration pass.

•

be fully acquainted with local conditions with respect to the potential hazards of radiological work on site and during transportation, storage and waste handling of radioactive substances.

•

notify management, via the BRUNEI SHELL JV COMPANIES where appropriate, of the existence of any condition or situation which may not normally be considered a radiation hazard, but may become a hazard under special or unusual circumstances.

•

advise management and/or the BRUNEI SHELL JV COMPANIES on the authorisation and training of persons for work involving ionising radiation.

•

advise management and/or the BRUNEI SHELL JV COMPANIES as to which persons shall be appointed as Classified Workers.

•

advise management and/or the BRUNEI SHELL JV COMPANIES on the implementation of the safety measures and personal protection devices to be used and on the selection of appropriate monitoring devices.

•

advise management and/or the BRUNEI SHELL JV COMPANIES with respect to the procedures and special equipment to be available in the event of an emergency, and on the need for emergency drills.

The services of the person appointed as RPO by a Contractor shall be available at all times.

2.2.2

Radiation Focal Point (RFP) For BRUNEI SHELL JV COMPANIES, the line (Contract Holder/Company Representative) may nominate a Person as Radiation Focal Point to be responsible for ensuring that the requirements stated in this document are met. The RFP should have as minimal attended the Safe Handling and Transportation of Radioactive Materials course and Radiation Safety Awareness course.


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The RFP is to ensure that the requirements are adequate and advise contract holders on incorporating into contract documents, and that control measures within line management are implemented and adhered to at all times (e.g. supervision, classification of workers, auditing, etc.) The RFP is responsible for acquiring and maintaining records and registers for Classified Workers and equipment.

2.2.3

Radiation Protection Supervisor (RPS) The criteria listed under this item apply to Contractor appointments. Qualification and Experience shall be as per BSP Standard 12-P-10. Medical shall produce previous radiation dose records and must pass a pre-employment medical examination given by an appointed medical doctor. An RPS of a Contractor shall be appointed by the Contractor RPO, accepted by the Contract Holder. All appointments and notifications shall be in writing. An RPS shall: •

Be registered with the DSS, Ministry of Health and possess a valid Industrial Radiation Worker Registeration pass.

•

Be in possession of an official nomination defining roles and responsibilities as set out in the Ionising Radiation Regulations SI 1985: No.1333.

•

Ensure that the ionising radiation safety standards are complied with and that the necessary working procedures, emergency procedures and procedures for registration/deregistration are set up and followed.

•

Be present where radioactive sources are used in order to ensure that protective measures and safe working techniques are observed.

•

As appropriate, inspect sites where radioactive sources are stored and inspect vehicles used for the transportation of these sources.

•

Provide advice and checks on ionising radiation safety standards, dose limits, monitoring, and appointment and discharge of Classified Workers.

•

Have the authority to implement emergency procedures.

•

Ensure his name and telephone numbers are prominently displayed at all sites where radioactive sources are used or stored.

2.2.4

Medical Officer A Medical Officer shall be appointed in accordance with the Shell Safety Committee “Ionising Radiation Safety Guide” (November 1993, Section 2.5.3) by any organisation which employs Classified Workers. For BRUNEI SHELL JV COMPANIES staff, the Chief Medical Officer at Panaga Hospital has been appointed. Contractors must appoint a suitable doctor to the position of Medical Officer and provide details of the appointee to the BRUNEI SHELL JV COMPANIES Contract Holder. Note: The Chief Medical Officer at BSP Panaga Hospital can provide advice on the appointment of a Medical Officer for radiographic purposes. The Medical Officer shall: •

Undertake medical examinations and maintain records of Classified Workers.

•

Examine any employee who receives a radiation dose greater than the designated limit as a result of an unplanned/excessive exposure to:

2.2.5

a)

determine any ill effect.

b)

determine if any personnel affected should be suspended from radiological work.

c)

determine date of work resumption, if appropriate.

Contract Holder The Contract Holder shall: •

Ensure that contractor appointment of RPO, RPS and Medical Officer are reviewed and approved.

•

Ensure that the contractor, the personnel involve with radiation activities and the contractor’s forwarding company are registered with DSS, Ministry of Health.


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•

Be responsible to review and approve Local Rules and Procedures.

•

Ensure that all requirements for work involving ionising radiation are implemented and adhered to by line management and by Contractors, including their Subcontractors.

•

Ensure that Classified Workers are identified and examined by the appointed Medical Officer as and when required.

•

Ensure that listings of X-ray equipment and registeration and de registeration records of radioactive sources are maintained.

•

Periodically audit for compliance. ( Refer to Appendix E ).

2.2.6

Asset Holder The Asset Holder shall: •

Ensure all appropriate measures are implemented and providing a satisfactory level of control to protect personnel from exposure to ionising radiation.

•

Ensure that Area Authorities appointed for the Asset under his control have been trained in radiation awareness.

•

Be responsible for approving procedures for operations involving the use of ionising radiation.

•

Ensure that a registration record of radioactive sources and radiation equipment at all operational sites are kept and maintained.

•

Ensure that radioactive storage areas and work areas involving the use of radioactive sources are properly identified, cordoned off with barriers, warning notices in English and Malay posted at all access points, and restrict entry to unauthorised personnel.

•

Ensure that LSA radioactive scale or sludge is identified, and the appropriate procedures taken to ensure safe methods of work.

2.2.7

Contractor The Contractor shall: •

Be responsible for the protection of workers, members of the public and also the environment. He shall ensure that none of the annual dose limits prescribed in this document will be exceeded for the protections of workers and members of the public.

•

Ensure that record of the Contractor and Ionising Radiation Worker, registeration certificate and pass respectively, are valid and up to date.

•

Ensure the provision of RPO and RPS(s) in accordance with the requirements set out in this document.

•

Ensure the provision and control of properly trained, competent Classified Workers.

•

Be fully responsible for the conduct of his subcontractors.

•

Be responsible for radioactive sources and radiation generators at all times.

•

Be responsible for the storage, transportation and safe handling of sources and radiation generators.

•

Ensure that his Local Rules and procedures pertaining to ionising radiation protection are complied with.

•

Periodically Audit for compliance. ( refer to Appendix E ).


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3

Module 20

LOCAL RULES The regulations upon which this standard is based requires every employer who undertakes work with ionising radiations to set down, in writing, Local Rules for the conduct of that work. Work with ionising radiations at BRUNEI SHELL JV COMPANIES locations is carried out by specialist Contractors and they shall, therefore, prepare Local Rules for their operations. This shall be carried out in consultation with the RPO and/or RPS. Local Rules shall contain as a minimum, but not limited to: •

Roles and responsibilities of the RPO and RPS(s).

•

Calculation models to calculate radiographic boundry and stay time, and it’s importance.

•

A description of each controlled and supervised area (see below). These areas sometimes exist only temporarily, for example during radiography, loading sources into wireline tools, or working with sludge or scale contaminated with LSA radioactivity. In such cases, the descriptions shall show how the controlled and supervised areas are to be determined (i.e. the measurements of dose rate and contamination levels) and their boundaries marked.

•

Written systems of work which give details of the procedures by which non-Classified Workers may work in controlled areas. Examples of situations which will require a written system of work are: 1.

entry to a controlled area around an installed instrument solely for the purpose of opening or closing its shutter.

2.

entry to a controlled area around the designated source store to carry out routine monitoring.

3.

carrying out work involving exposure to LSA radioactive scale.

•

Procedures for restricting access to controlled areas, e.g. supervision, warning signs, signals, etc.

•

Contingency plansfor each BRUNEI SHELL JV Companies, work area, either on or offshore.

•

The names and designations of persons appointed as RPA, RPS(s) and Competent Persons.

•

The strategy for monitoring dose rates and contamination levels.

•

Any additional requirements to ensure safe operations at all times and to limit exposure to non-radiological workers and members of the public.

A complete set of Local Rules from each Contractor required to prepare them shall be held by the contract holder. Copies shall be made available to employees who may be affected by the work. Controlled and Supervised Areas The following definitions which are also reproduced in the Glossary, are based on the definitions given in the regulations upon which this standard is based, namely SI 1985: No. 1333 (Part III Designation of controlled and supervised areas) Controlled Area

A defined area in which doses of ionising radiation are likely to exceed three-tenths of any specified dose limit.

Supervised Area

A defined area in which doses of ionising radiation are likely to exceed one third of the limits specified for a Controlled Area.


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4 4.1

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RADIOLOGICAL OPERATION Personnel All personnel shall : •

Comply with all BRUNEI SHELL JV COMPANIES requirements relating to the use of radioactive sources, including full adherence to written procedures relating to individual operations.

•

Cooperate in implementing safe systems of work to minimise the risk of exposure to ionising radiation.

•

Report to their supervisors any deficiencies noted in the control of ionising radiation sources.

•

Understand the meaning of radiation warning symbols/signs and the requirement to restrict access to controlled areas.

Note: Individuals below the age of 18 years shall not be involved in radiological work.

4.2

Contractor Only Contractor registered with the Radiation Laboratory (Department Of Scientific Services, Ministry of Health) shall be allowed to carry out ionising radiation operations within Brunei Shell JV Companies. Record of contractor’s registeration shall be submitted to the contract holder. Before the Contractor commences any ionising radiation work, the contractor shall provide a copy of their written local rules to the contract holder for approval as described in Section 3. The Contractor shall make the written appointment of an RPS with overall responsibility within the Contractor’s organisation. The appointment shall be notified to the appropriate BRUNEI SHELL JV COMPANIES Contract Holder. The Contractor RPS will act as the first point of contact for action on radiation safety matters. The name and telephone numbers of the Contractor RPS shall be prominently displayed at all sites where radioactive sources are used or stored. The Contractor RPS must be present at the worksite to supervise the application of the appropriate radiation protection regulations, and procedures. In addition he shall administer and maintain relevant records required by BRUNEI SHELL JV COMPANIES. The Contractor RPS shall liaise with the BRUNEI SHELL JV COMPANIES RFP and Asset Holder on all matters concerning the execution of ionising radiation work.

4.3

Classified Workers All persons who are likely to exceed a radiation dose which exceeds three-tenths of any relevant dose limit, shall be Classified Workers. They shall be specially trained in the safe use of radioactive sources, particularly those who work with little supervision at remote sites, and certain of them shall be authorised to carry out specific activities. All Classified workers shall be registered with the Radiation Laboratory (Department of Scientific Services, Ministry of Health) and record of registration submitted to the contract holder. Classified Workers shall undergo a medical examination by the appointed Medical Officer prior to commencing work at the beginning of a contract term and at periods determined by the Medical Officer. Classified workers shall: •

Wear a film badge/TLD at all times when working with radioactive sources and radiation generators;

•

Have ready access to a personal dose meter;

•

Wear audible alarm monitors if directly involved with radiation of high output scales.

•

Report immediately to the RPS the loss of a personal dosemeter.


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•

Ensure that their status as Classified Workers is conveyed to medical personnel during either routine or accident treatment so that dose rates are taken into account.

•

Verify that their personal dose record is adequately controlled and follows them to successive employers.


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4.3.1

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Industrial Radiographic Team The team shall consist of a Radiographer and an assistant Radiographer who are the Classified Workers having a valid Industrial Radiation Worker Registration Pass. The qualification and experience shall be as per BSP Standard 12-P-10. i)

Radiographer

can have dual role as an Radiographer and a Site RPS provided the qualification and experience as stipulated in BSP Standard 12-P-10 are met. He shall ensure the role of RPS on site are implemented in proper manner. The appointment as site RPS in writing shall be from an RPA in the same organisation.

ii)

4.4

Assistant Radiographer

to assist a Radiographer.

Equipment All equipment shall be maintained in good, clean, working order, and be checked regularly by an RPS at each site. A record of these checks shall be kept, showing details of any defects found and the actions taken to remedy them. Equipment shall be examined annually. All equipment shall be provided with the means of preventing unauthorised use. When not in use or in transit, all equipment shall be kept in a locked store reserved exclusively for radioactive materials, so as to minimise the risk of its coming in to the possession of unauthorised or untrained personnel. Where necessary and to ensure safety at all times, all equipment (e.g. containers) is to be inspected/tested by independent, external bodies

4.5

Safety Equipment Appropriate monitoring equipment, e.g. portable survey meter, audible alarm, pocket dosemeter, film badge/TLD and warning signs shall be used at all times whenever radioactive substances are stored, transported or used. The issue and control of personal monitors and dosemeters for contractor personnel shall be the responsibility of the Contractor whereas for BRUNEI SHELL JV COMPANIES Classified Workers, the responsibility is with the Department Head. The maintenance of safety equipment and warning devices shall include their regular testing to confirm as far as is reasonably practicable that they are capable of fulfilling the particular purpose for which they are required to be provided. Failure in this equipment tends to be failure to danger.

4.5.1

Portable Survey Meter These should be light, robust and capable of being used in all weather under arduous conditions. Their response shall be appropriate for the type of radiation used and be able to cover a suitable range, e.g. 0 - 500 mSv.h-1, with reasonable accuracy.

4.5.2

Audible Alarms (Bleepers) Audible alarms are small and lightweight, designed to be carried in the top pocket of a shirt, jacket or coverall. They must be kept switched on during the whole period that the wearer may be exposed to high output scales. These shall be able to indicate the presence of radiation by an audible signal and give immediate warning of a high dose rate. They shall also be capable of emiting a recognisable signal at a dose rate of 100 microSv.h-1 plus or minus 50%.

4.5.3

Thermoluminescent Dosemeter (TLD) A TLD is based on the principle that a certain material (phosphor) can absorb and store radiation energy and remain stable at room temperature. A TLD is able to emit light in proportion to the amount of energy absorbed from the radiation. The accuracy of dose measurement by TLD can be as good as plus or minus 5% with a minimum repeatable dose of about 0.1 mSv.


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4.5.4

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Film Badge The film badge is an item of individual monitoring equipment and works on the principle that radiation exposes photographic film; the darkening of the film by the radiation is relative to the dose received by the wearer. The accuracy of dose measurement by film allows a minimum reportable dose of 0.1 mSv.

4.6

Low Specific Activity (LSA) Radioactive Scale LSA radioactive scale originates when naturally occurring salts precipitate from produced water. The radioactive scale can occur in any part of a production system, from wellbore to separator. The scale contains radio nuclides of the uranium 238 and thorium 232 series, which emit alpha, beta and gamma radiation. Potential hazards from this type of radiation arise when well tubulars are pulled or items of the process train are opened or dismantled. Contaminated dust could then be inhaled or ingested and pose a serious health hazard. Strict monitoring and control procedures must be followed when handling radioactive scale. LSA radioactive scale has not yet been encountered in significant quantities in BRUNEI SHELL JV COMPANIES operations; if or when it is, specific procedures for working with equipment contaminated by LSA scale shall be prepared and integrated with Hazard Identification Plans. NOTE: Refer to HSE Module 40 – Occupational Health & HSE Module 19 – Hazardous Substances for further details on handling these scales.

4.7

Safe Distance Prior to carrying out ionising radiation exposure, an initial calculation to determine the safe distance boundary shall be carried out before preliminary boundary is established. Since radiation dose rates diminish with the inverse square of the distance, one method of protection is to increase the distance between persons and the radiation source. Remotely operated equipment or handling tools which enable separation between the source and the worker shall be used at all times for the manipulation of radioactive sources. The typical length of X-ray equipment cables or windout cables for radiography containers shall not be considered as an adequate safe distance. Direct contact between source and the body, e.g. hands, must be prevented under all circumstances.

4.8

Shielding For radiography sources, collimators shall be used wherever possible. In order to limit scattered radiation, additional shielding shall be considered, for example by means of mobile protective lead screens. Scatter radiation from X-ray generators shall be limited by the use of collimators and back shielding. When working on site, all available radiation obstructions such as pipes and concrete walls shall be used to reduce exposure to radiation dose rates. Information on new developments in radiation shielding should be addressed to the Contract Holder.

4.9

Exposure Time The time during which personnel are exposed to radiation shall be kept to an absolute minimum. Classified Workers shall pre-plan their activities to minimise the time spent in controlled areas. Prior to carrying out an ionising radiation activity, the stay time for using a particular source strength shall be calculated for the following conditions; a)

at 1 metre from source

b)

at designated controlled area.

The practice of applying a shift system in order to distribute the received radiation dose amongst Classified Workers involved is not permitted.


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4.10 Working with Ionising Radiation Sources a)

On offshore platforms and other restricted working areas, radiography shall be carried out during shiftwork hours, during the the night or at mealtimes, whenever possible, to minimise the risks to other employees.

b)

The Permit to Work Procedure shall be used for all operations involving ionising radiation. The relevant BRUNEI SHELL JV COMPANIES Authorised Person shall ensure that the source strength, type and registration number are recorded on the permit. The Worksite Supervisor shall use the Radiography Safety Checklist (form 25/HSE) during preparation of the permit. For further information, refer to HSE Standard Module 03 - Permit to Work Procedure.

c)

In addition to the Radiography Safety Checklist the Radiation Supervisor shall prepare the Site Location Plan, showing the defined boundary dose rate, shielding mechanism if used, location of the warning sign and/or accessories and source container and remote windout control location.

d)

Work shall be carried out in a suitably marked area and enclosed by a barrier of rope or bunting set up at no greater than the 7.5 µSv.h-1 boundary. Flashing lights shall be used to mark the barriers where work is carried out at night. The lights shall be appropriately certified for use with regard to Hazardous Area classification.

e)

At certain times during radiation work, the 7.5 µSv.h-1 boundary level may have to be exceeded due to the constraints of production or of space. These exceptions shall be kept to a minimum and the approval of the Asset Holder obtained. The 7.5 µSv.h-1 level may also be exceeded during preparations for well logging. This shall only be a transient excursion while the tool is moved and before it is positioned downhole. This can be accepted with the support of HIP. Every attempt shall be made to keep the levels to a minimum and nonessential personnel are clear of the area.

f)

Warning signs in both Malay and English shall be posted at the boundaries to exclude all but authorised Classified Workers. The notices shall be not less than 80cm x 50cm in size, shall display the radiation warning symbol as specified in BS5378 and shall include the name, address and contact telephone number of the site RP0/RPS. (See Figure 2).

g)

No drinks or food shall be allowed in controlled areas.

h)

When establishing controlled areas, Contractors shall ensure that monitoring is carried out at the floor levels above and below the area involved to ensure radiation dose rates are not being exceeded.

i)

When ionising radiations are being used, particular attention shall be paid to the location of ultra-violet flame detectors or other devices which may be affected and require to be inhibited prior to the start of work. If in doubt, contact the appropriate Area Authority.

j)

In addition to marking the boundaries, adequate warning shall be given to all in the vicinity. An announcement shall be made over the public address system before radiography or logging starts, stating the areas affected and the likely duration of the work.

k)

Further warnings are required when radiography work is carried out. These shall take the form of a pre-warning immediately before the source is exposed and a separate warning during source exposure. The requirement to give a pre-warning is important, so that people who may be inside the radiation areas can clear out in good time. An acceptable system is for a whistle to be blown during the pre-warning phase and for flashing lights to be used during the source exposure.

l)

Frequent monitoring shall be carried out during radiography or logging work to ensure that the dose rate at the barriers is not being exceeded. This shall be done by the Contractor. On occasions the authorised person appointed by the Contract Holder shall check the dose rates at the barriers using the installation monitors.

m) Some radiographic work involves the use of projection-type containers where the radioactive source is wound out, either manually or mechanically, to the end of a projection tube. The source can stick in the projection tube and radiation overdoses have occurred as a result. A monitor shall be used to confirm that a radioactive source has been wound back into its container. n)

Safety is enhanced by limiting the number and total activity of available ionising radiation sources on the location. In normal circumstances, no radioactive source larger than the equivalent of those shown below shall be kept on location: Offshore

- 925 GBq (25 curies) Iridium 192

Onshore

- 1295 GBq (35 curies) Iridium 192


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BLNG

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- 925GB (25 curies) Iridium 192

Note: If for any reason a BRUNEI SHELL JV COMPANIES Contractor requires to use a larger source, this requirement shall be referred to the Contract Holders who must liaise with and obtain approval from the BRUNEI SHELL JV COMPANIES.


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Figure 2 - Typical Radiation Warning Signs

4.11 Change of Radioactive Isotopes Only with the approval of the Contract Holder shall a change of radioactive sources be carried out. The operation shall be carried out or supervised by an RPS in accordance with an approved procedure. An approved container for source changing shall be used and after radioactive sources have been changed, dose rate measurements shall be carried out to manufacturers recommendations.

4.12 Dose Limits The Shell Safety and Health Committee recommends that, in general, the International Commission on Radiological Protection (ICRP) dose limits are adopted for the use of Shell Companies and therefore: •

The effective dose shall not exceed 20 mSv over one year. This limit is in usually referred to as “ THE EFFECTIVE DOSE LIMIT “.

•

For pregnant women, a dose limit to the surface of the woman’s abdomen of not greater than 2 mSv shall be applied for the remainder of the pregnancy.

4.13 Recommended Target In addition to respecting the effective dose limits for BRUNEI SHELL JV COMPANIES operations defined above, BRUNEI SHELL JV COMPANIES shall aim to ensure that for employees of BRUNEI SHELL JV COMPANIES and Contractor companies, individual occupational exposure shall be controlled such that: The average annual effective dose received as a result of employment as a Classified Worker shall not exceed 2mSv, where averaging over defined periods of 5 years is allowed.

4.14 Dose Limits for Members of the Public This standard is intended to enable the protection of BRUNEI SHELL JV COMPANIES and its Contractor's employees against occupational exposure to ionising radiation. BRUNEI SHELL JV COMPANIES management shall also ensure that BRUNEI SHELL JV COMPANIES activities do not cause the dose received by members of the public to exceed 1 mSv per annum. In this respect it shall also be noted that non-radiological workers are considered to be members of the public.


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5 5.1

REGISTERS

Module 20

AND

RECORDS

Register of Classified Workers The names of all BRUNEI SHELL JV COMPANIES and Contractor personnel designated as Classified Workers shall be entered in a “Radiation Dose Register”. Contractors shall maintain their own register and copy it to their Contract Holder and Medical Officers accordingly.

5.2

Personal Radiation Dose Records The results of personal dosemeter assessments for all Classified Workers shall be entered into personal radiation dose records which shall be kept by the employer for two years after termination of employment and for 50 years by an approved dosimetry service. The original records shall be released and forwarded to the next employee location when the person concerned is transferred. Copies of these records shall also be forwarded to the employee.

5.3

Radioactive Source Register All radioactive substances in the possession of a Contractor at a location shall be registered and contain the following information: •

type of radioactive substances;

•

sealed or unsealed sources;

•

radio nuclide identification number;

•

container number

•

activity (shall not be greater than 45Ci at time of entry into Brunei);

•

date of receipt;

•

location when in storage;

•

date and method of disposal (if appropriate).

Every source shall be positively identified by use of a BRUNEI SHELL JV COMPANIES registration/de-registration form (see Figure 3). Registration with Contract Holder shall be within 14 days of receipt and deregistration when the activity level is below 4Ci. The registration / deregistration proposal shall include an approved Importation and Exportation permit from DSS, Ministry of Health respectively. Mobile sources for site radiation work shall be logged in and out of store on each occasion they are used. The presence of all sources on a location must be checked on a weekly basis if periods between use are greater than one week. The results of this check must be recorded (see Figure 4). Sources surplus to requirement shall be disposed of by return to their manufacturer. Registration is effected in various ways: a)

All mobile radioactive apparatus, e.g. the equipment used by contractors, has to be registered with the BRUNEI SHELL JV COMPANIES Contract Holder. This is the responsibility of the Contract Holder and Contractors. It is also a condition of registration that an RPS is in charge of the equipment at all times and that a copy of the Registration Certificate is available on site or installation and a copy sent to the BRUNEI SHELL JV COMPANIES Contract Holders.

b)

For permanent radioactive sources, e.g. those in level gauges or Beta lights, the premises require to be registered rather than the equipment. Nearly all these sources are the property of Contractor(s) and the Asset Holder shall consult the BRUNEI SHELL JV COMPANIES Contract Holder. The necessary registration certificates will then be obtained and copies sent.

c)

Where unsealed sources are to be used, the premises require to be registered no matter how small the activity of the source.


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Figure 3 - BRUNEI SHELL JV COMPANIES Registration/De-registration Form

Certain small sources do not require to be registered. These include: •

Sources less than 100 Bq (3nCi) in activity;

•

Radioactive sources incorporated into fire detectors;

•

Small Betalights such as in the Range Load Indicators fitted to cranes.


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Figure 4 - Specimen Site Isotope Weekly Record

5.4

Register of X-ray Equipment This register, which is kept and administered by PML, shall contain the following information:

5.5

•

make and type of equipment;

•

maximum tube voltage of the equipment;

•

location where equipment is stored.

•

next inspection/calibration due date.

Leak Testing and Inspection Records These records must contain: •

the date and results of leak testing carried out on radiography containers;

•

a description of the method used.

•

next inspection due date.


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5.6

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Purchasing Records In order to control the use of X-ray equipment and radioactive substances on site, such equipment or substances shall be purchased only after approval from the RFP. It is recommended that this process includes some provision for approval of the intended application.

5.7

Radioactive Substance Transfer The following logs (registers) of radioactive substance transfer must be kept for each BRUNEI SHELL JV COMPANIES operating location: a)

A Register to be kept by the Contractor recording the movements of all radioactive substances on and off the installation or site.

b)

A register kept by each Contractor, recording the movements and locations of their own sources used on the installation or site. This must be made available to the BRUNEI SHELL JV COMPANIES IRPA upon request.

Each register shall show the following: •

The distinguishing number or other identifiable mark of the substance;

•

The date of receipt on the installation;

•

The nature of the radioactive substance, e.g. Caesium 137 or Iridium 192;

•

The activity of the radioactive substance expressed in Becquerels and Curies;

•

The date the radioactive substance is taken off the installation.

Entries in the register must be made immediately the source is taken out of or returned to storage. A specimen Radioactive Substance Transfer Record form is shown in Figure 5. Figure 5 - Specimen Radioactive Substance Transfer Record


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5.8

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Records of Disposal The disposal of radioactive sources shall be carried out in accordance with the adopted legislative requirements. Radioactive waste differs from all other types of waste. Its radioactive strength decreases only with time and its properties cannot be altered or destroyed by any physical, chemical or biological treatment. Sealed sources constitute the majority of radioactive substances used in BRUNEI SHELL JV COMPANIES operations and the only waste disposal connected with a source is the disposal of the source itself. When the strength of a source has decayed to the point where it can no longer be used for its intended purpose, it shall be returned by the Contractor to the original manufacturer/supplier for disposal. Note: Damage to a sealed source may result in radioactive waste in the form of contaminated equipment, packing and other accessories.


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Definition of what constitutes radioactive waste and recommendations on the handling of radioactive waste are contained in the Shell Safety and Health Committee "Ionising Radiation Safety Guide".


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6 6.1

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STORAGE Storage Offshore On offshore Installations, the following requirements for radioactive source storage must be met: a)

All radioactive materials, when not in use, shall be kept securely in an exclusive store or “dog kennel”. Well logging and radiography equipment should be kept separate. Note: Transport containers may not afford sufficient shielding to act as permanent stores. Once a transport container is on deck, the radioactive contents shall be transferred to the permanent store without delay, unless the transport container is specifically designed to also act as a store.

b)

The store shall be fitted with sufficient safety signs in indelible print in both Malay and English, and the signs shall include the name, address and contact telephone number of the RPO/RPS appropriate to the location of the store.

Figure 6 - Typical Source Container for Offshore Transportation and Storage

6.2

c)

The store shall not be placed in an area where in the event of damage it is likely to restrict access to fire points, lifeboats, helideck or emergency equipment and be kept at a place as far as reasonably practicable from any hazardous areas and any living accommodation.

d)

The store shall be located such that it can be recovered during an emergency situation and it shall have at least a 5m separation from any explosives store or locker.

e)

The store should be monitored regularly by a competent person appointed by the contractor. If the surface dose rates are being exceeded then the matter should be taken up with the contractor RPS without delay and brought to the attention of the Contract Holder.

f)

In the event that the RPS or competent person is working on a day visit basis, the key to the store shall be in the possession of the Toolpusher or Senior Operations Supervisor, as appropriate.

g)

Details of ionising radiation material on location shall be noted in the main control room/office.

Storage Onshore At onshore locations, radioactive sources shall be stored in a storage pit which shall be: a)

Situated in a quiet part of the site away from any vehicular or pedestrian traffic.


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b)

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A vertical steel tube 450mm to 600mm diameter and about 1.5m to 1.8m long and plate thickness minimum 10mm with a welded base sunk into the ground with sufficient protrusion to enable a securely hinged lockable steel lid to be fitted.

Figure 7 - Typical Arrangement for Source Storage Pit

c)

With a “coat hanger” type bracket fitted inside the tube near the top so that the isotope containers may be lowered by means of a rope tied to the bracket to facilitate subsequent removal. The whole assembly should be waterproof.

d)

Maintained clean and free from debris at all times to prevent fire.

e)

Enclosed at a distance of at least 1.5m by a fence with a lockable gate and the keys for the enclosure and storage pit held by an authorised person.

f)

With an effective dose rate outside the storage place in areas accessible to members of the public not exceeding 1 µSv.h at a distance of 1.0m.

g)

Fitted with sufficient safety signs or warnings in indelible print in both English and Malay at the lockable entry to the cage. Names and telephone numbers of the Company’s RPA or RPS shall also be displayed for use during an emergency.

A survey meter shall be made available to provide early detection of high dose rates.


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7 7.1

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TRANSPORTATION General Requirements X-Ray equipment is not hazardous unless it is switched ON. For this reason, no special precautions are necessary for transport and storage other than ensuring the security of the equipment. Radioactive sources cannot be switched off and depend on the shielding of their containers to render them safe. The integrity of these containers is therefore vital. The requirements for packaging, labelling and consignment certificates are the same whether the goods are being transported by road, rail or air. It is usually the consignor’s responsibility to comply with transport rules. The Contract Holders must be consulted if Contractor(s) are to transport their own radioactive substances.

7.2

Labelling All packages containing radioactive substances must be labelled with one of the three types of label described and illustrated below. Minimum two labels are required for a package. They should be attached on the opposite sides of the package for better indication. This applies even if the source or substance is exempt from registration (see Section 5.3). Category I White

A diamond shape in black and white with one red strip. It shall be used when the dose rate does not exceed 5 µSv.h-1 (0.5 mR/h) at the surface.

Category II Yellow A diamond shape in black, white and yellow with two red strips. It shall be used when the dose rate does not exceed 500 µmSv./h (50mR/h) at the surface or 10 µmSv/h (1mR/h) at a distance of 1 metre. Category III Yellow A diamond shape in black, white and yellow with three red stripes. It shall be used when the dose rate does not exceed 2 mSv./h (200mR/h) at the surface and 100 µSv.h (10mR/h) at a distance of 1 metre. Note: Nearly all radioactive substances sent to BRUNEI SHELL JV COMPANIES sites or installations will carry yellow labels. Figure 8 - Transport Labels

Category I


Category II

Category III

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Figure 8a –Vehicle Transport Label

7.3

Packaging The consignor must ensure that the package is of the correct standard for the radioactive substance to be carried. There are two types of package: Type A packages are designed to prevent loss or dispersal of the radioactive contents and to retain shielding under normal conditions of transport which includes minor mishap, e.g. falling from the tailboard of a lorry. Type B packages must in general meet Type A requirements and in addition, be designed to withstand severe accident conditions including fire. Type B packages shall be used for all transportation of radioactive substances by air and sea. Figure 9 - Type B Source Container Secured for Transit

The type shall be clearly marked on the outside of the package and any Type B package must be of a design approved by a competent authority in the country of origin. A copy of the certificate of approval must accompany the package.

7.4

Consignment Certificates The consignor shall issue a consignment certificate, a copy of which shall be attached to the package with a further copy attached to the manifest. The consignment certificate shall contain the following information: •

Consignor’s name and address;


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•

Package identification number;

•

Type of packaging;

•

Description of radioactive content (isotope activity, physical or chemical form);

•

The maximum dose rate in mSv.h-1 divided by 10 mRh-1 at one metre from the surface. This is known as the Transport Index.

Note: The Transport index has no units. The transport index label shall be attached to the transporting metal container. A survey meter shall be available. If at any time it is considered that the labelling or packaging is not satisfactory then the Contract Holder or BRUNEI SHELL JV COMPANIES RFP shall be consulted for advice.

7.5

Transport by Air The requirements for transport by air are laid down in the UK Air Navigation (Dangerous Goods) Regulations. They state that dangerous goods can only be carried by air in accordance with the current International Civil Aviation Organisation (ICA0) Technical Instructions. As International Air Transport Association (IATA) regulations incorporate all the ICA0 Technical Instructions, compliance with IATA regulations will fulfil legal requirements. No distinction is made between fixed wing aircraft or helicopters. The rules follow the principles of labelling and packaging described earlier. following shall be taken into account:

In addition the

•

The Air Waybill must be marked to indicate that radioactive substances are being carried.

•

Packages bearing white or yellow labels must not be carried in compartments occupied by passengers and crew.

•

The minimum distance that radioactive packages may be kept from the passenger cabin/flight deck boundary is given in table 9, Part 2B, Section 10 of the IATA Regulations.

•

The total sum of the Transport Indices shall not exceed 50 with a limit of 10 per package.

All types of source currently in use offshore can be carried in accordance with IATA Regulations on helicopter flights if required. The IATA Dangerous Goods declaration form shall be completed prior to consignment.

7.6

Transport by Sea The requirements for transport by sea are laid down in the UK Merchant Shipping (Dangerous Goods) Regulations. Adherence to the International Maritime Dangerous Goods (IMDG) Code or the Department of Trade (UK) “Blue Book” will satisfy the requirements of the Regulations in relation to radioactive substances. Larger quantities of radioactive substances can be carried by ship and the total sum of the Transport Indices can be as large as 200 but must be arranged in groups so that the sum of each does not exceed 50. Radioactive substances must be carried in different holds from explosives, inflammable or corrosive substances. If radioactive packages are to be placed in large freight containers for sea transport, the containers shall be labelled and marked in exactly the same way as the original package.

7.7

Transport by Road The requirements of Brunei Traffic Laws and the Radioactive Substances (Carriage by Road) (Great Britain) (Amendment) Regulations shall be met. The following are general requirements for any vehicle carrying radioactive materials: •

At least 2 portable fire extinguishers (9kg size) of the dry chemical powder type to be installed in the vehicle.

•

The vehicle must be labelled with the international radiation symbol (Figure 8a) securely attached to each side of vehicle.

•

A fireproof notice to warn fire services, police, and others in the event of an accident shall be displayed and give the following information in English and Malay:


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-

Type of radioactive source being carried;

-

Telephone numbers of the Contractor RPS for emergency contact;

-

Telephone numbers of authorities to be contacted in the event of an emergency.

The placard shall be removed when no radioactive consignment is being carried. Figure 10 - Source Container Transportation by Vehicle

7.8

•

All such vehicles should carry at least one spare tyre and a tool kit for emergency repairs to the vehicle

•

The level of radiation in the driving compartment and at any external surface of the vehicle shall be as low as reasonably achievable and in the case of the driver and any passengers who are not Classified Workers, shall not exceed 2.5 µSv.h-1.

•

The driver must not leave any vehicle containing radioactive material unattended or out of sight, without reasonable cause. In all cases, the vehicle must be locked and/or the package otherwise secured against removal.

•

Any vehicle containing radioactive material must not be parked for more than ONE hour unless there is a clear space of at least 2 metres all around the vehicle when it is parked.

•

The driver of a registered contractor or forwarding agent must be fully briefed by the Contractor’s RPS and must have attended the course on safe handling and transportation of radioactive materials conducted by the Ministry of Health. .

•

The Driver & Vehicle must also comply with the Land Transport Manual, TMS 0711 Manpower Standard, and TMS 0439, Vehicle Standard.

Transportation Incidents The packages and containers used to protect radioactive substances in transit are specially designed to withstand the effects of fire and collision damage. If, however, it is discovered that the package is damaged and possibly leaking, the following actions shall be taken: •

Do NOT attempt to remove the load;

•

Keep members of the public away from vehicle (except where saving of life is involved);

•

Set up barriers around the affected area;

•

Contact Company/Contractor RPS;

•

Keep the Consignment Note to hand;

•

Liaise with emergency services when they arrive on site;

•

Inform the relevant Contract Holder and HSE Department;

•

Take names of persons suspected of being contaminated.


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All suspected over-exposures must be medically examined as directed by the Contract Holder or appointed Medical Officer.


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8 8.1

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REFERENCES Brunei Darussalam Legislation Procedure for Importation, Exportation, Transportation, Storage and Use of Radioactive Sources or Industrial Radiography Equipment

8.2

United Kingdom Legislation, Regulation, etc. The Health and Safety at Work (etc.) Act 1974 The Radioactive Substances Act 1993 The Ionising Radiations Regulations SI 1985: No 1333 and Approved Code of Practice (ACOP) Code of Practice for the Carriage of Radioactive Materials by Road - Department of the Environment The Merchant Shipping (Dangerous Goods) Regulations SI1981: No1747 The Air Navigation (Dangerous Goods) Regulations SI1985: No1939

8.3

International References International Atomic Energy Authority (IAEA) Safety Series No 6 Regulations for the Safe Transportation of Radioactive Materials 1985 The International Air Transport Association (IATA) Restricted Articles Regulations The International Civil Aviation Organisation (ICAO) Document 9284 AN905

8.4

SIEP Shell Safety & Health Committee “Ionising Radiation Safety Guide” November 1993. SIPM Radiation Safety Manual for Well Logging Operation issued in September 1991, Report EP91-1645.

8.5

BRUNEI SHELL JV COMPANIES BSP Drilling Operations Engineering Completion Manual, Bulletin 4915.4 (1994) Custodian TSW/5 BSP Emergency Co-Ordination Procedure Manual HSE/1.

TMS 0358 and TMS 0359 - Custodian

HSE Standard Module 03 - Permit to Work Procedure. HSE Standard Module 30 - Incident Classification and Reporting. HSE Standard Module 31 - Incident Investigation Procedure. Guidelines of Transporting Dangerous Goods by Air, Sea and Land. BLNG PTW Manual HSEQ- 202 BSP Land Transport Manual 14.2


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Module 20

APPENDIX A - GLOSSARY

OF

TERMS

GLOSSARY Activity (A)

The attribute of a quantity of a radionuclide. Describes the rate at which nuclear transformations occur within it. Unit of measure is becquerel, symbol Bq. 1Bq = 1 transformation per second. (Pre-SI unit of measure: curie, symbol Ci. 1Ci = 3.7 x 1010 Bq)

Becquerel (Bq)

The unit measure of activity. transformation per second.

One becquerel equals one nuclear

1Bq = 2.7 x 10-11 Ci Collimator

A device used to reduce the radiation level emitted from a radioactive source, except in the desired direction.

Controlled Area

A defined area in which doses of ionising radiation are likely to exceed three-tenths of any specified dose limit.

Decay

The process of spontaneous transformation of a radionuclide, i.e. the decrease in activity of a radioactive substance.

Dosemeter

A device used to detect and measure ionising radiation, e.g. a pencilsize ionisation chamber with a self-reading electrometer. Used for personal monitoring.

Exposure

A measure of the ionisation produced by X or Gamma radiation.

Film Badge

A pack of photographic film which measures personal radiation exposure. The badge may contain films and filters to measure different types of radiation.

Gonads

The organs producing reproductive cells in humans and animals, i.e. ovaries and testes.

Gray (Gy)

A unit denoting the quantity of energy imparted by ionising radiation to unit mass of matter such as human tissue. Unit of measure is Gray. One Gy = one joule per kilogram.

Half-life

The time taken for the activity of a radionuclide to lose half its value through decay.

IAEA

International Atomic Energy Agency.

ICRP

International Commission on Radiological Protection. ICRP-26 was the basis for the September 1983 Shell Ionising Radiation Safety Guide. ICRP-60 of 1990 set new dose limits as a result of review of risk factors, and redefined several radiological protection concepts. It forms the basis for the current Shell Ionising Radiation Safety Guide.

Ionisation

The process by which a neutral atom or molecule acquires or loses an electrical charge. The production of ions.

Ionising Radiation

Radiation that produces ionisation in matter. Types are alpha particles, beta particles, gamma-rays, X-rays and neutrons.

Local Rules

No two work sites have exactly the same combination of layout, activities and personnel and because of these differences and their significance in the context of radiography, local rules are required for each site. The rules must describe each controlled and supervised area, specify the requirement for Permit control of work and cover all systems of work for the specific location. Local rules are drawn up in consultation with the RPA.


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LSA Scale

Low Specific Activity Radioactive Scale internal walls of tubulars, pipes and originates in the naturally-occuring salts are released by the chemicals added to reservoir for pressure maintenance.

is scale deposited on the vessels. Its radioactivity in an oil reservoir and they the water injected into the

Natural Radioactivity

Terrestial sources of natural radiation are the very long-lived radionuclides that have existed within the Earth since its creation. Another source is the high-energy radiation that enters the Earth's atmosphere from outer space, the so-called cosmic rays.

NDT

Non-Destructive Testing of components and equipment using techniques such as dye penetration, ultrasonics or radiography.

NRPB

National Radiological Protection Board of UK. An independent public authority set up in response to legislative requirements to advance knowledge on the protection of mankind from radiation hazards and provide advice to persons with responsibility for radiological protection.

Radiation Monitoring

Periodic or continuous determination of the quantity of ionising radiation or radioactive contamination present. Area Monitoring is the determination of radiation levels or contamination in a particular area, building, room or piece of equipment. Personal Monitoring is the determination of radiation levels or contamination for an individual, his breath, excretions or any part of his clothing.

Radioactive Waste

Useless material containing radionuclides. Frequently categorised according to activity and other criteria, e.g. low level (LSA), intermediate and high level waste. The disposal of radioactive waste is subject to international legislation.

Radiological Protection

The science and practice of limiting the harm to human beings from radiation.

IRPA

Independent Radiation Protection Advisor. An organisation or an approved person providing advisors and conducts Radiation audits for BRUNEI SHELL JV COMPANIES.

RFP

Radiation Focal Point. The appointed person within a BRUNEI SHELL JV COMPANIES department or division who has been nominated by line management as the point of contact on radiation matters.

RPA

Radiation Protection Adviser. The appointed person responsible for providing specialist advice on the subject of radiation protection.

RPS

Radiation Protection Supervisor. The appointed person responsible for the area in which work with ionising radiation is being carried out.

SI

The abbreviation for Systeme International d'Unites (International System of Units), the measuring convention based on the primary units of mass (kilogram), length (metre) and time (second).

Sievert (Sv)

The unit of effective dose equivalent, it has the dimension of joules per kilogram. The dose equivalent in Sieverts is numerically equal to the absorbed dose in Grays multiplied by the quality factor.

Supervised Area

A defined area in which doses of ionising radiation are likely to exceed one third of the limits specified for a Controlled Area.

TLD

A thermoluminescent dosemeter badge constructed from material which, having been irradiated, releases light in proportion to the radiation absorbed when subsequently heated.

X-rays

Discrete quantities of electromagnetic energy without mass or charge. Energy contained much higher than that of visible light. Usually produced by bombarding a metallic target with fast electrons in high vacuum, as occurs in an X-ray machine. In some countries, X-rays are called Rontgen rays.


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APPENDIX B - RADIOACTIVE SUBSTANCE INCIDENT CHECKLIST All incidents involving radioactive substances must be reported and investigated in accordance with BRUNEI SHELL JV COMPANIES HSE Standard Module 30 - Incident Classification and Reporting; and BRUNEI SHELL JV COMPANIES HSE Standard Module 31 - Incident Investigation Procedure. Examples of incidents are: •

Wearing expired film badge;

2

•

Film badge not being worn;

2

•

Vehicle carrying a radioactive substance without Radiation Hazard warning Signs displayed;

•

2

Vehicle displaying Radiation Hazard warning signs found parked in shopping area for coffee break;

3

•

Radioactive source left unattended on site during coffee or meal break;

3

•

Batteries for survey meter found not fully charged;

2

•

Entering site without survey meter;

2

•

Transporting radioactive source without a competent person in attendance;

3

•

No labelling on package containing radioactive substance;

3

•

Permit to Work not displayed on site;

3

•

Public seen walking through a supervised area in which a radioactive substance is being used;

2

•

Fire detectors activated by exposure of a source;

2

•

No warning signs set up at entrances to the work site.

3

Potential Severity The potential severity of an incident is determined by reviewing the circumstances leading to the incident and assessing the potential consequences to personnel, assets and the environment should the incident recur. The assessment is done on the basis of what might reasonably have happened and requires the application of experience and common sense. It is not possible to provide fixed guidelines on how to determine potential severity. For radiation incidents, potential falls into two categories: 1.

Risk of monitoring injury.

2.

Increased risk of cancer.

Severity factors are given against each of the incident examples shown above.


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APPENDIX C - RADIATION PROTECTION GUIDELINES Any activity which takes place in the potentially hazardous environment of the oil and gas industry must be properly planned, organised and managed if it is to take place without incident. These guidelines provide information which may be useful both in operational management and in the preparation of Local Rules, by either BRUNEI SHELL JV COMPANIES or its Contractors, for application in the conduct of activities involving ionising radiation. Topics which need to be addressed include the following: •

Assessment of potential health hazards to workers and members of the public.

•

Assessment of safety features and devices in the design and construction of an installation or facility.

•

Formulation and implementation of Operational Rules and Procedures for the safe operation of the installation or for safe working practice. The inherent protection provided by the design of the installation must always be supplemented by actions taken by the operator or worker to protect himself. Well defined operational procedures, local rules and instructions shall be formulated and personnel involved in the operation with ionising radiation must be familiar with, and must observe, these procedures, rules and instructions.

•

Establishment and implementation of personnel and area surveillance and, where appropriate, environmental surveillance. Personnel surveillance includes personnel monitoring and assessment of radiation dose and medical or health surveillance. The appropriate devices to monitor and assess the radiation dose of the individual worker under normal and emergency conditions shall be provided. The results of personnel dose monitoring and assessment shall be used to verify adequacy and effectiveness of the protective measures in ensuring that the doses received by the workers are as low as reasonably achievable and do not exceed dose limits. The medical surveillance of personnel shall comprise of periodic medical examinations and in cases of over exposure, special medical attention as recommended by the Medical Officer. Medical surveillance is necessary to ensure that the health of the worker is not adversely affected by his work and that no worker continues to be employed contrary to qualified medical advice. Area Surveillance - Appropriate instruments and techniques shall be made available for monitoring external radiation and radioactive contamination in the working areas under normal and emergency conditions. Besides regular monitoring, radiation measurement shall also be made during the commissioning of a new installation and when modifications are made to existing installations which are likely to affect the radiation protection parameters. Environmental surveillance of areas outside an establishment where radiation sources are used or stored is necessary to ensure that the radiation doses to members of the public do not exceed dose limits. Depending on the operations within the establishment, it may be necessary to conduct periodic or special surveys. When justified by the nature and scale of the operations, appropriate instruments and techniques should be made available for the monitoring of external radiation or radioactive contamination outside the establishment under normal and emergency conditions. Appropriate effluent monitoring is necessary when radioactive dusts, aerosols, gases or liquids may be released in sufficient amounts to the environment.

•

Provision for checking and calibration of radiation monitoring instruments. All monitoring instruments must be checked for compliance and shall be calibrated at annual intervals, as per manufacturers’ guidelines or by approved standard laboratories.

•

Establishment of a system for the collection and maintenance of relevant records. All records relevant to radiation protection shall be kept and maintained in an appropriate manner to facilitate their effective retrieval and utilisation. Among the important and relevant records to be kept and maintained are the following: -

Inventory of radiation sources.

-

Personnel dose records.

-

Medical examination record.

-

Area monitoring data.

-

Environmental monitoring data.


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•

-

Effluent monitoring data/waste disposal records.

-

Inventory and record of monitoring instruments.

-

Report of unusual occurrences.

Module 20

Formulation of Emergency Plans and Procedures. Emergency situations may arise following incidents involving the sudden loss of control over radiation sources. In order to minimise the consequences of an incident, it is necessary to determine the potential sources of accidents and their possible consequences. Based on this analysis, emergency situations may be classified according to the nature and degree of hazards involved and the appropriate plan and protective actions for the mitigation of the adverse effects arising from an accident. Note: All incidents including near-misses must be reported and investigated according to the BRUNEI SHELL JV COMPANIES HSE Standard Module 30 - Incident Classification and Reporting ; BRUNEI SHELL JV COMPANIES HSE Standard Module 31 - Incident Investigation Procedure.

•

Establishment of Training Programmes for Personnel. The authority in charge of an establishment shall ensure that suitable and adequate training is provided by the Contractor to all employees involved with ionising radiation. The initial training shall include topics such as hazards involved in the work, principles and practices in radiation protection, safe working procedures, the correct use of monitoring devices and emergency procedures and techniques. Further training should include specific instruction in the method of operation of every item of equipment the worker is likely to use in the course of his work and this is particularly important for source exposure equipment. Classified Workers must also be taught to recognise fault conditions and other potential emergency situations, and to operate the BSP emergency procedures. At least once a year, Classified Workers should practice source recovery techniques under the direction of the RPA, using a dummy source. Retraining at appropriate intervals is necessary to ensure the continuing competence of workers to protect themselves and their colleagues. Classified Workers shall have a formal qualification in handling radioactive substances and shall attend the relevant HSE Training.


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APPENDIX D - IONISING RADIATION EMERGENCY PROCEDURE 1

Administration Full details of emergency responses are contained in BSP Emergency Co-Ordination Procedures (TMS0358 and TMS0385). The emergency response flowchart from these procedures is reproduced at the end of this appendix. For every contract for the provision of ionising radiation services, the Contract Holder and Contractor shall prepare specific emergency procedures as part of the requirement for Local Rules and these procedures shall be regularly reviewed and updated. The RPS appointed by the contractor for the site or installation shall be fully trained and equipped to take immediate action in an emergency, to ensure that no person is exposed to avoidable radiation. He shall have the skill and knowledge of contingency plans and have suitable equipment available. It is not intended that the BRUNEI SHELL JV COMPANIES RFP shall carry out the emergency procedures listed below but he should be aware of the requirements and be available to provide assistance. He shall also carry out regular checks of the contractor’s emergency equipment to ensure that it is complete and in working order. These emergency procedures will normally apply when a radioactive source becomes detached or lost on an installation. If a radioactive source or tool is lost down the hole during well logging, the BSP authorised person and the Asset Holder in charge shall be informed at once. There will normally be no need to invoke further emergency procedures. Most radiation incidents are due either to a source failing to return to a projection type radiography container at the end of an exposure, or to a source becoming separated during or after use. Because the work shall be isolated within a suitably marked area, there will already be barriers in position and since radiation monitors are being used, the presence of an unshielded source should be apparent immediately. Experience has shown that when this happens, quite large sources can be brought into a safe condition without anyone receiving an excessive exposure. In the event of an emergency which cannot be managed with the resources available on site, the following actions shall be taken: ONSHORE •

Evacuate the affected area,

•

Isolate the affected area,

•

Contact the Contractor RPA or RPS for technical advice.

•

Call Panaga 37-2999 and state: -

the nature of the emergency,

-

the location of the emergency,

-

your name and telephone number,

-

action already taken.

OFFSHORE •

Evacuate the affected area,

•

Isolate the affected area,

•

Contact the Senior Operations Supervisor (SOS),

•

Contact the Contractor RPA or RPS for technical advice,

•

Establish communications with VSL and state: -

the nature of the emergency,

-

the location of the emergency,

-

action already taken.


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Emergency Equipment The minimum requirements are: -

Audible alarm monitor.

-

Quartz fibre electrometer and charging device or other integrating dose meter.

-

Handling tongs.

-

Flashing Lights (i.e beacons)

-

Pliers.

-

Screwdriver.

-

Adjustable spanner or wrench.

-

Other hand tools which are appropriate for the particular equipment.

-

Bags of lead shot (2kg per bag), for which at least two are required for radiography sources.

-

Approved Emergency Container.

The following items are used to hoist up the end of a projection tube to help return a detached source to its container by gravity :

3

-

Tripod 2 metres high.

-

Ropes.

Action If The Source Has Become Separated a)

Access to the vicinity must be restricted wherever practicable by a barrier set at a distance where the dose rate does not exceed 7.5 mSv.h-1. If barrier materials are not available, “sentries” shall be posted where the barrier shall be, allowing each to remain in position for not more than a total of 2.5 hours. Radiation warning notices and flashing lights must be displayed at the barrier position. No person shall be allowed to pass the barrier except those engaged in recovery or rescue operations. Any person who may have been inside the restricted area shall be identified.

b)

Measure the radiation intensity with a dose rate meter. If the meter has developed a fault or is not immediately available it shall be assumed that the source is completely unshielded.

c)

Inform the Asset Holder or RFP immediately of what has happened, the action proposed and the help required.

d)

Plan a course of action outside the barriers. If possible, practise the proposed operations on similar equipment. Collect long handling tongs, shielding materials, hand lamps, etc. in readiness.

e)

The time spent by each person in the emergency action must be kept to a minimum. In high dose rate situations, substantial doses can be received when approaching and leaving an exposed source. If at all practicable the emergency action shall be limited to one approach. This is why planning is essential.

f)

If possible, replace the source into the container. Use the long handling tongs and work quickly, keeping all parts of the body at arm’s length from the source. DO NOT PICK IT UP WITH BARE HANDS. A second person must stand at the barrier to time the work and indicate when the permitted time has expired. Check with a dose rate meter that the source is back in the container.

g)

If a radiation source cannot be replaced in its container, then lead bricks, or layers of sheet lead, or bags of lead shot shall be placed over the source to attenuate the radiation. If these materials are not available, then sand or similar materials can be used though they are not as effective. In the case of a neutron source, drums of oil/water or paraffin shall be used instead.

h)

At all times, care shall be taken to keep all parts of the body at arm’s length from the source. Remember the area underneath may require shielding also. It is then essential to keep the barriers, warning signals and notices in position until assistance arrives, allowing no person, except competent persons, to enter the controlled area.


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5

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Action If The Source Has Been Returned To The Container a)

Check the shielding.

b)

Check the fastenings of the container, especially if the source has accidentally become separated from its container.

c)

Remove the workers involved in the recovery operation from radiation work until their doses have been established.

d)

Send the personal dosemeters worn by all workers involved for urgent examination, explaining the reasons.

Action If The Source Is Still Outside The Container a)

Check that the barriers, warning signs and notices are satisfactory and that no unauthorised persons are in the controlled area and that persons supervising the barriers are not receiving excessive radiation.

b)

Make a further planned attempt to return the source to its container using the same precautions as before. If this attempt fails, decide whether or not it will be possible to return the source or if it will be necessary to obtain another container. In the latter case, the contingency plans mentioned earlier shall be initiated .

c)

When the second container arrives, place the source in it and decide whether the source can be returned to normal use, or whether disposal action is necessary. If it is considered necessary to remove the container from the installation, then the BRUNEI SHELL JV COMPANIES RFP and the Asset Holder shall be informed.

Source Lost Offshore In the event of the loss of a source, the following action is required: a)

The loss must be immediately reported to the RPS appointed by the Radiography or Well Logging company, the Toolpusher and the BRUNEI SHELL JV COMPANIES Authorised Person.

b)

Urgent action must be taken to monitor and establish safe areas where personnel can assemble.

c)

All personnel coming into an area must be monitored to establish whether or not the source has become lodged in their clothing. The Tool pusher and the competent persons between them shall establish priorities in the monitoring of personnel. First monitor those most likely to have been in contact with the source.

d)

Once the monitoring has been carried out, a search shall be undertaken by the contractor’s competent person under the overall direction of the Asset Holder. Safe areas must be established as the search proceeds, priority being given to living quarters and then to process areas where work cannot be shut down.

e)

If the source is located reasonably quickly, then the emergency procedures detailed earlier shall be adopted. If the source cannot be located, then the search shall be continued, paying particular attention to drains, pipes, etc. which may shield the radiation.

f)

If it is still not possible to locate the source, advise the BRUNEI SHELL JV COMPANIES Contract Holder or appropriate line department, and the Contractor RPS who will arrange for assistance to be provided as required.

g)

If the helideck and surrounding area is clear, then there in no reason to suspend helicopter flights, provided goods and persons going to the helicopters are monitored.

h)

It is recommended that no goods be put out from the platform by sea until the source is found. Note: In the event that a source is lost in a well, the procedures detailed in the Drilling Operations Engineering, Completion manual, bulletin 4915.4 should be followed. (Available from TSW/5)

7

Source Lost Onshore If a radioactive source container with or without a radioactive source is missing or suspected of being stolen: a)

Make an immediate search.

b)

To locate a radioactive source, use radiation detection equipment.


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c)

If the source is not found within an hour, inform the RPS, the BRUNEI SHELL JV COMPANIES RFP and the Police.

d)

If a vehicle containing a source is missing, immediately inform the Police, the BRUNEI SHELL JV COMPANIES RFP and the BRUNEI SHELL JV COMPANIES RAC.

Incident Reporting and Investigation In all cases of incidents involving ionising radiation, make a full investigation of the circumstances, taking written statements from the employees involved, including details of where they were in relation to the source and for how long. Obtain similar information from any other persons who may have been exposed. If it appears likely that an excessive exposure may have occurred, notify BRUNEI SHELL JV COMPANIES supervisor or direct to RPS and report the incident in accordance with BRUNEI SHELL JV COMPANIES HSE Standard Module 30 Incident Classification and Reporting; BRUNEI SHELL JV COMPANIES HSE Standard Module 31 - Incident Investigation and Procedure.


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Module 20

APPENDIX E - IONISING RADIATION SAFETY REVIEWS 1

Purpose The purpose of an Ionising Radiation Safety Review is to measure the level of compliance with safety standards that is being achieved by the people involved in work with radioactive substances and identify areas where improvements can be made. Reviews are an integral part of the Contract Holder and Contractor’s HSE Plan as part of their Safety Management System.

2

Scope of Review Reviews are conducted both by BRUNEI SHELL JV COMPANIES and Contractors. The scope of a review shall include all relevant documentation for the personnel involved, the equipment used, the radioactive substances in use, their storage and transportation, and the controls for their use. The validity of the documentation is then verified by site or work area inspection which is also used to observe and note safety techniques and practices in use. Reviews and inspections are not limited to the Contractor and his employees; Contract Holders and site or installation supervisory personnel are also included on aspects of safe work control.

3

Review Team Depending on the nature of the review, the team will be drawn from the members of the BRUNEI SHELL JV COMPANIES Contract Holder which may coopt others into the team.

4

Review Schedule The timing of Ionising Radiation Safety reviews by Contractor and Contract Holder will be planned a year in advance. In special circumstances, for example a follow-up review after finding significant areas for concern during the initial review, it may be conducted outwith the plan. Reviews shall be conducted at least once every twelve months in each of the Brunei Shell Companies where radioactive substances are in use and carried out in accordance with terms of reference agreed by the BRUNEI SHELL JV COMPANIES RFP. Where there is particular concern over operations involving the use of radioactive substances, a review may be initiated by the Contract Holder in conjunction with the relevant Asset Holder. Contractors carry out their own reviews and are encouraged to invite the Contract Holder, RFP or any member of the BRUNEI SHELL JV COMPANIES to observe their audits or inspections.

5

Review Procedure Ionising Radiation Safety review procedures are to be an integral part of a Contractor’s Safety or Quality Management System and it is a contractual requirement that a copy must be forwarded to the BRUNEI SHELL JV COMPANIES Contract Holder and verified as part of the Managing HSE in Contracts process. Confirmation that a scheduled review is to take place will be given to all the personnel involved at least a week in advance of its start. On being notified, Radiography Contractors shall assemble all relevant documentation and records and prepare them for scrutiny. A site inspection checklist should be available, and a specimen checklist is shown in Figure A. Members of the review team shall be supplied with personal monitoring devices such as film badge/TLD, personal dosimeters and survey meters before entering any site where work with radioactive substances is carried out. Radiation level readings shall be taken at various areas such as radioactive storage containers and exposure rooms by using calibrated dose rate meters. Work practices shall be observed, equipment inspected and Classified Workers interviewed.

6

Reporting Assessment of performance shall be based on: -

SIPM Ionising Radiation Safety Guide issued in Nov 1993.


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-

BSP HSE Standard Module 20 - Ionising Radiation Safety.

-

BSP Managing HSE in Contracts .

-

Other relevant BRUNEI SHELL JV COMPANIES HSE Standards.

Module 20

The review report, with findings, recommendations and suggested remedial actions, will be discussed and actions agreed with the Contract Holder and Contractor Representative(s) before it is released. Copies of the report will be given to the Contract Holder, the Contractor concerned, appropriate BRUNEI SHELL JV COMPANIES Management, and appropriate Asset/Service Unit HSE Adviser.


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APPENDIX F -

Module 20

RADIOACTIVE SUBSTANCES INFORMATION

A) Substances Used at BRUNEI SHELL JV COMPANIES Sites Radio nuclide

Symbol

Use

Activity (GBq)

Package Type

Americian 241

Am/Be

Compensated

185 - 740

111 Yellow

Beryllium

Neutron Log

Americian 241

Am/Be

Calibration

14.0

111 Yellow

Caesium 137 Log

Cs

Formation Density

72.0

111 Yellow

Caesium 137 Log

Cs

Fluid/Cement

3.70

111 Yellow

370

111 Yellow

Beryllium

Density Log Cobalt 60 72 -

Co

Radiography (Occasional)

Iridium 192

Ir

Radiography

Up to 1110

111 Yellow

Ra

Calibration

92.5 x10-6

1 White

In

Tracer

92.5 x10-6

111 Yellow

I

Tracer

92.5 x10-6

111 Yellow

Iodine 131

I

Tracer

92.5 x10-6

111 Yellow

Scandium 46

Sc

Tracer

92.5 x10-6

111 Yellow

Technetium 99M

Te

Tracer

92.5 x10-6

111 Yellow

Tritium H

T

Betalights/Tracer

Up to 629.0

111 Yellow

Radium 226

-6

Radium 113M Iodine 125

-6

-6


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Module 20

B) Types of Radiation and Required Shielding

Alpha Particles Beta Particles

Gamma rays Neutron X-Rays

Travel approximately 75mm in air and can be absorbed by as little as a sheet of paper. Most Beta radiation can be absorbed by 12.5 mm of plastic, e.g Perspex, but since beta particles can cause electromagnetic radiation which is more penetrating, additional shielding may be necessary. Dense materials such as lead and steel, or considerable thicknessesof concrete or brick may be required. Substances with a rich content of hydrogen such as paraffin waxpolythene or water are required, oil may be used in an emergency. Are generated electrically by machine. The intensity of the beam depends on the current & volt set on the machine. The machine does not give off ionising radiation when it is switched off. The characteristics of X-rays are similar to Gamma Rays therefore the shielding required is of the same material.

C) Dose Effect Relationships Following Acute Whole Body Irradiation

Whole body dose (Gy) 0.05 - 0.25

0.25 - 1 1-3

4.5 >6

> 50


Clinical and laboratory findings Asymptotic, conventional blood studies normal, a very small number of chromosome aberrations detectable above 0.1 Gy. Asymptomatic, minor depressions of white cells and platelets detectable in a few persons on day 3 - 6. Anorexia, nausea, vomiting, fatigue in about 10 to 20 per cent of persons within 2 days. Depression of white cells (lymphocytes) and platelets on day 3 to 6. Progression in second and third week and chance of infection and bleeding. Above 3 Gy hair loss on day 9. Recovery in week 4 to 6. Serious, disabling illness in most persons with about 50% mortality. Accelerated version of acute radiation syndrome with gastrointestinal complications, bleeding, infections and death in most exposed persons within 2 weeks. Fulminating course with gastro intestinal, central nervous and vascular complications resulting in death within 24 to 72 hours.

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Ionising Radiation Safety Procedure

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