13VesselEntry ppt use in confined space entry
- 1. Safety Talk On Confined Space
- 2. Entry into a confined space is a hazardous activity in the oil and gas business. Entry permit systems have been in place for years but fatal accidents continue to happen. An entry permit, by itself, does not make entry safe. Briefings and discussions like this are essential: • To maintain awareness • To learn the lessons from past accidents • To add local knowledge to the Company’s procedures Workplace safety depends on people factors ! Why discuss entry ?
- 3. A confined space is any space with limited access and escape, where flammable or toxic vapours could collect, or where the oxygen content could be reduced What is a confined space ? Some spaces are obviously confined eg. process vessel Others are less obvious eg. open- topped / floating roof tank, pit, sump, excavation > 1.5 m. deep Other specific locations may be designated as confined spaces by site management Note that ‘entry’ includes putting your head inside an enclosed space eg. for visual inspection Can you add to the list ?
- 4. Risks of entry Failure to identify confined space Failure to isolate the vessel Failure to isolate internal appliances eg. mixers Exposure to explosive, toxic or asphyxiating atmosphere Exposure to hazardous materials Risks associated with work in a confined space eg. fumes Inability to exit quickly in emergency Risk from activities outside the vessel
- 5. Risk assessment Plan and think through the work in advance, involving all the relevant people including specialists (Ops, Maintenance, HSE) Is entry essential, or can the work eg. inspection be done from outside ? All practical means must be employed to make the vessel safe from the outside before entry is permitted The entry permit system is then used to control entry
- 6. What is an entry permit ? An entry permit is a ‘contract’ between the operating authority and the performing authority, covering: Responsibility for all aspects of the entry Definition of the vessel, location, and permit validity Isolation, and preparation of vessel and workplace (Gas) test results Remaining hazards and precautions including monitoring Completion and withdrawal of permit Distribution of permit copies ensures all interested parties are informed Safety Talk 8A / 6
- 7. Working in a confined space An entry permit is not a permit to carry out work Additional cold, hot, electrical permits are required as appropriate, cross referenced to the entry permit Each work permit must cover the additional hazards of working in a confined space
- 8. • Shut down and removal of oil and gas hazards by depressuring, draining etc. • Positive isolation* by disconnection or blanking as near to vessel as practical • Valve(s) isolation is not adequate • Isolation of heating coils and driven internal appliances *If positive isolation is impractical, entry is prohibited without special dispensation from senior management Decommissioning / isolation
- 9. Preparation of worksite Warning notices posted and vessel clearly marked for entry Good access and escape provided Separate access ways for services, hoses, cables etc All means employed to make vessel safe from the outside before entry permitted Remove surrounding (<15m) hazards eg. seal drains Vessel purged and ventilated
- 10. Gas testing Gas testing to be carried out, by competent person, for oxygen, flammable and toxic gas (in that order) Test equipment of suitable design, regularly inspected, tested/ calibrated and maintained Limitations of equipment and test method recognised High risk areas identified and checked Tested from outside initially, and then inside
- 11. Entry without Breathing Apparatus (BA) Conditions required: Gas test results: – Oxygen 20.8% (as atmospheric air) – Flammable gas less than 1% LEL – Toxic gas less than 10% OEL (8 hours exposure) All traces of oil, sludge, scale etc removed Conditions not expected to change Adequate ventilation to maintain atmosphere If not met, further risk assessment must be done
- 12. Entry with suitable BA Guidelines: – Oxygen 19.5% to 23.5% volume – Flammable gas < 10% LEL (entry), 20% LEL (exit) – Toxic gas < STEL (15 mins exposure) BA wearers must have been specifically trained and accredited Outside the above limits the atmosphere inside the vessel must be considered life threatening
- 13. Life threatening atmospheres An entry permit must not be issued to enter a life threatening atmosphere Entry under inert gas eg. catalyst removal under nitrogen: • Only specialist contractors will enter and work in inert atmospheres, with authorisation from senior site management
- 14. Summary of gas test levels OXYGEN FLAMMABLE TOXIC Without Breathing 20.8% <1% LEL <10% OEL Apparatus (BA) With BA subject 19.5 - 23.5% 10% LEL to enter <STEL to risk assessment 20% LEL exit Unsafe <19.5% >20% LEL >STEL or >23.5% OEL (Occupational exposure limit – for 8 hours exposure) STEL (Short term exposure limit – for 15 minutes exposure)
- 15. • Coordination and segregation of work to prevent dangerous interactions, particularly for complex work • Restrictions on work to be carried out externally and internally • Adequate internal lighting suitable for zone 1, and where possible < 25 volts • PPE to be worn Precautions against remaining hazards
- 16. Entry permit issue and distribution Entry permit form fully completed and issued by operating authority to performing authority Permit distribution ensures that the required information is formally communicated to all interested parties Original to the performing authority, to be posted at the entrance to the vessel Copies to – Control room or other operating centre – Operations supervisor – HSE dept – Others as decided by site management
- 17. Entry Tags Tags are used to: Reinforce the entry permit Warn that hazardous conditions exists – see entry permit Prohibit entry
- 18. PERFORMING AUTHORITY Supervisor visits worksite • Holds a ‘toolbox talk’ with those who will carry out the work • Additional briefing for contractors and subcontractors • Explains scope, restrictions, timescale, precautions, first aid and emergency procedures • Considers factors relating to the specific day • Gives clearance signature to enter • Is present when entry first made OPERATING AUTHORITY Supervisor visits worksite Commencement of entry
- 19. Monitoring Repeat gas tests or continuous gas monitoring Position Vessel Entry Standby’s immediately outside the confined space – at least one with SCBA if worn for entry Control over routine access / exit should be maintained If conditions change, in an emergency, and if the general alarm sounds, persons must be able to exit quickly EVERYONE has a duty of care to those inside the vessel ANYONE can and must raise the alarm to evacuate the vessel if they detect a hazard to the people inside
- 20. Vessel Entry Standby duties Remain on duty until relieved Maintain an accurate count of all persons in the vessel Maintain effective contact with the persons inside the vessel Use a life-line where appropriate Monitor activities to confirm that it remains safe for people to remain inside Order evacuation if conditions change to endanger people inside Summon rescue services in an emergency Do not enter
- 21. Emergency action and rescue Entry must cease if the emergency siren sounds First action is to raise the alarm and summon the emergency services Only specially selected, fit, trained rescuers can attempt rescue. Untrained persons MUST NOT ATTEMPT RESCUE • Self contained breathing apparatus (SCBA) must be used • If work or entry is stopped for safety reasons, it must not be restarted until all tests and checks are repeated and written authorization given
- 22. Permit validity Validity rules will be set by site management according to the risks involved and the working/shift system Entry permits should not be valid for more than 1 work period or day All ‘live’ entry permits must be formally handed over at working/shift changeovers, together with a status update
- 23. Completion of entry Performing authority signs and returns the original entry permit to the operating authority Operating authority inspects the vessel and, if satisfied, withdraws the permit The original permit form should be filed for future reference All copies should be filed or destroyed to ensure that only valid permits are ‘live’ in the workplace
- 24. Higher risk work Entry which cannot be carried out in accordance with the entry permit system: – where gas test criteria cannot be achieved – where disconnection or spading is impractical – other entry permit rules cannot be met Involves more detailed planning and control procedures outside the scope of this safety talk Requires authorisation by a senior manager
- 25. Wrong equipment A contractor entered the cage of the wrong air cooler, through a trap door locked with a padlock and key. Unfortunately the padlock was in a bad condition so he cut it off. Luckily the fan was not started while he was inside.
- 26. ‘Mixed up’ Electrical isolation must be positive lock-out/ tag out Each vessel should have an isolation list There is no substitute for walking around a vessel, physically checking each connection, and verifying positive isolation A worker cleaning the inside of a vessel was killed when the (wrong) mixer was inadvertantly started.
- 27. ‘Boxed in’ Workers cleaning trays in a column were working from the bottom to the top. Others ‘boxing up’ man ways were working top to bottom simultaneously to save time. Luckily frantic banging raised the alarm, and the cleaners were released.
- 28. Attempted rescue If the mate had called for help he may have saved the worker’s life as well as his own A worker collapsed inside a vessel. His mate attempted to rescue him, without raising the alarm, but was also overcome. They were both found dead some time later.
- 29. ‘Putting your head in’ An operator put his head into the tank opening of a barge to check the oil level. He was overcome and fell inside the tank and was killed. A maintenance foreman put his head inside a manhole on a nitrogen purged vessel to check details of internal fittings. He was found collapsed (dead) over the manhole.
- 30. ‘Putting your head in’ again A welder was repairing cracks in the man way of a tank that had been nitrogen purged. Work was not possible with the manhole cover in place. He dropped a torch tip into the tank, looked inside for it, collapsed, fell in and died.
- 31. Enhanced combustibility A fire broke out inside a Hortonsphere when tarpaulins and scaffolding boards caught fire as a result of enhanced combustibility due to oxygen leaking from cutting equipment (1 man killed).
- 32. Pride comes before a fall Attempting to unplug a tank pump suction, a contractor entered the tank through a small opening, wearing only a cannister respirator. There was no entry permit and he was instructed not to go in. He would not come out even when felt dizzy. He was killed by benzene vapours.
- 33. Dangerous interactions The permit system should tell us all the work and entry that is happening at any point in time Large / complex jobs and or worksites have to be broken down into manageable parts When preparing for hot work, ‘vapour – free’ does not mean ‘gas free’ A contractor was carrying out hot work on an overheads line resulting in an internal fire – fuel was probably gas oil distilled over during steaming out. The fumes migrated to the column overcoming unprotected workers carrying out familiarisation training (2 deaths).
- 34. ‘I thought’ (that I knew better) Another (forbidden) rescue attempt An employee was cleaning the inside of a storage tank. Instructed to use a steam cleaner but used solvent because he thought it would be quicker. He was working unsupervised. He knocked over a container of solvent and was overcome by vapours. A second person, who entered the tank without breathing apparatus, was also overcome
- 35. Competency, training and awareness Workplace safety depends on: Awareness, communications, training and supervision Care and competence of those responsible for the work Competencies should be • Defined in terms of skills and experience required • Training and experience given • Confirmed by formal testing and accreditation eg. operating and performing authorities, gas testers, vessel guards Workplace safety depends on PEOPLE
- 36. Contractor s Contractors should receive training in the work permit system as part of their induction Contractors workers may also require: Specialist training eg. in wearing/using breathing apparatus Medical examinations to confirm physical fitness
- 37. Summary Entry is one of the higher risk activities carried out in our refineries We have pointed out the risks, and the controls that are available in the permit system The permit system is one of the critical controls used to establish and maintain a safe workplace An entry permit: – is a contract between the Operator and the Performer – defines responsibilities, scope and timing of work – raises awareness and provides a useful checklist / aide memoire A permit alone can never make entry safe Only the care and competence of those who operate the system can do that
- 38. Optional quiz 1. Managing risk involves (4 steps) 2. Name 4 inherent hazards of entry 3. Is valve isolation adequate for entry ? 4. What important roles does the (operating) supervisor play ? (4) 5. What important roles does the (performing) supervisor play ? (4) 6. What important roles does the standby person outside a vessel play ? (4) 7. What should you do if you discover a hazard that compromises the safety of entry ? (2) 8. What should you do if you discover a person in difficulty in a confined space ? 9. What checks would you make if asked to enter a vessel ? 10. How can we generate interest and maintain awareness of everyday safety issues ? (any ideas would be welcome)
- 39. Work permit process/responsibilities 1 Before work starts Permit required (Yes, no, type) Application for a Work Permit: Define work scope Identification of the hazards of performing the work Joint planning of work with the Area Authority Decisions on isolation Decommissioning Joint planning of work with the Performing Authority Coordination with other work Identify hazards associated with facility operations Raise and complete the appropriate permit form(s) Receive Work Order A P P E N D I X 1 OPERATING AUTHORITY PERFORMING AUTHORITY
- 40. Preparation of worksite environment Preparation of worksite for the work to be done Review permit (Hot, Entry and Contractors) and accept Issue permit Review the completed permit form and authorise Specifying precautions Interpretation of gas results and decision on proceeding Arranging for gas testing (by accredited gas tester) Carry out isolation Preparation of equipment A P P E N D I X 1 OPERATING AUTHORITY PERFORMING AUTHORITY Work permit process/responsibilities 2
- 41. Permit distribution Post original permit at worksite Commencement of work Commencement of work Final inspection Post copy of permit at reporting point Tool box talk for work team Brief operating personnel A P P E N D I X 1 OPERATING AUTHORITY PERFORMING AUTHORITY Work permit process/responsibilities 3
- 42. Performing work Complying with restrictions Implementing precautions Monitoring the work related hazards Restart work Reissue permit Withdraw permit Commencement of work Commencement of work Monitoring eg. gas monitoring Entry Guard, Fire Watch Monitoring of workplace operating hazards Emergency and Rescue Suspension of work, uncompleted or interrupted work A P P E N D I X 1 OPERATING AUTHORITY PERFORMING AUTHORITY Work permit process/responsibilities 4
- 43. Completion of work Sign off permit Withdrawal of Permit Completion of work Handover at shift and personnel changes Handover at shift and personnel changes Stopping work if conditions change making work unsafe Clear workplace of tools, equipment, materials & workers Hand back the equipment in a safe condition to be recommissioned Inspection of completed work A P P E N D I X 1 OPERATING AUTHORITY PERFORMING AUTHORITY Work permit process/responsibilities 5