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Appendix G. Confined Space Entry Procedures

1. Determine if entry into confined space is necessary to perform work.
2. Minimum required equipment should be on hand: Ventilation, barrier and warning signs, gas monitor capable of measuring concentrations of oxygen, flammable gases, hydrogen sulfide and carbon monoxide.
3. Eliminate any unsafe conditions before the access door or cover is opened.
4. Immediately guard the entry by some barrier and signs to prevent people or objects from accidentally entering the confined space.
5. Conduct hazard assessment:

   Test the real or potential atmospheric hazards .

   • Oxygen content less than 19.5% or greater than 23.5%
   • Flammable gases and vapors greater than 10% of the LEL (Lower Explosive Limit)
   • Hydrogen Sulfide concentrations greater than 10 ppm (Parts per million)
   • Carbon Monoxide concentrations greater than 35 ppm
   • Other toxic gases or vapors greater than PEL (Permissible Exposure Limit)

   See Air Monitoring Guide for more information (Appendix B).

   Review the space for other observable serious safety and health hazards: mechanical, electrical, burn, heat stress, engulfment or entrapment hazards, etc.

6. If any hazardous atmosphere exists, do the following:

   a) If possible, determine and eliminate the source of the atmospheric hazards (for example: carbon monoxide from nearby truck or gas-powered generator).
   b) When the atmosphere contains toxins or flammables, ventilate the space by drawing air out until the air has been changed over several times.
   c) When oxygen deficient, ventilate by pushing air into the space until the air has been changed over several times.
   d) Verify the hazardous atmosphere has been eliminated by testing the air as in Step 5.

   See Ventilation Guide for more information (Appendix C).

7. Determine from information gathered above which entry procedure is appropriate:

   a) NON-PERMIT SPACE: If there are neither real nor potential atmospheric hazards and no observable serious safety and health hazards, this should be certified in writing. Certify by signing at lines 1 and 2 on Permit/Certification. After Certification, skip to step 13.

   b) ALTERNATE ENTRY PROCEDURES: If no observable serious safety and health hazards exist and atmospheric hazards are controlled with continuous ventilation, this should be certified in writing. Certify by signing at lines 2 and 3 on Permit/Certification.

   c) PERMIT-REQUIRED SPACE: If there are any observable serious safety/health hazards in addition to potential or real atmospheric hazards, all procedure here must be followed. Authorize Permit by signing on line 3.

   d) NON-RESPIRABLE ATMOSPHERES: If hazardous atmosphere cannot be eliminated by continuos ventilation, contact ORCBS before continuing.

8. Pre-entry precautions:
   a) Notify affected departments of service interruption.
   b) Lock-out/tag-out all sources of energy (e.g. steam, electric, mechanical) posing a risk to workers.
   c) Install blank in affected pipes where valves are not secure or seated.
   d) Clean and/or purge any chemical storage vessel.
   e) Wear appropriate personal protective and respiratory protection.
   f) Have lights and or ladder available.
   g) If coordination is needed with contractors, see Contractor Checklist.
   h) Have appropriate MSDS's (Material Safety Data Sheet).
   i) Determine how often air monitoring will be conducted.
9. Additional precautions necessary for Permit-Required Spaces:
   a) Determine start and end times for authorized entry.
   b) Assign roles and responsibilities as entrant(s), attendant(s), leadworker(s).
   c) Set up non-entry rescue equipment (tri-pod, harness).
   d) Identify rescue service.
   e) Determine communication method between entrant/attendant.
   f) Conduct pre-entry briefing: review hazards, procedures and precautions.
10. Sign and post the Permit/Certification at the site.
11. Continually ventilate the space by pushing air so that a positive pressure changes the air over several times every hour. Direct the clean air toward the worker.
12. Test the air periodically while personnel are in the confined space to ensure the ventilation is preventing any accumulation of a hazardous atmosphere.
13. Under the following condition, personnel must exit the confined space, re-evaluate hazards and modify entry procedures.
    a) If any hazardous atmosphere is detected after entry, Notify ORCBS before re-entry.
    b) If any health or safety hazard develops which was not anticipated.
    c) If Attendant (on Permit-Required Confined Space Entry) cannot effectively perform duties.
    d) If personnel in confined space are experiencing symptoms from heat stress or over-exposure to atmospheric hazards.
14. When work is completed, return the space to original condition.
15. Close out the permit/certification and submit the completed paperwork to your supervisor.

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