What is a permit required confined space (PRCS)?

Many confined spaces are associated with serious safety hazards, and require special procedures to ensure worker safety.
According to 29 CFR 1910.146, a permit-required confined space (or permit space) is a confined space that contains hazards capable of causing death or serious physical harm.
Besides the basic three conditions common to all confined spaces, a permit-required confined space contains at least one additional serious or recognized danger such as:
- The potential to contain or generate a hazardous atmosphere, (such as oxygen deficiency from rusting metal, combustible methane from decomposing leaves or debris, or hydrogen sulfide from sewage).
- The space contains a material that has the potential for engulfing an entrant (anything from water, to mud, to wood chips, to molasses).
- An internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section (such as many bins, chutes, and dust collectors).
- Any other recognized serious safety or health hazard (from rotating blades or vanes, to venomous snakes).
It is important to always remain on the lookout for conditions or activities that may change the dangers associated with a confined space. Activities such as hot-work, using degreasers, or painting may introduce additional potential hazards that change the classification of the space from a non-permit to a permit-required confined space (PRCS).
Permit space entry team members can only function effectively and safely when they fully understand their responsibilities and duties. Thorough training is essential. Permit spaces are by definition inherently dangerous – mistakes are not permitted!
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Written by Bob Henderson | President

Bob Henderson is President of GfG Instrumentation, Inc. in Ann Arbor, Michigan.Robert has been a member of the American Industrial Hygiene Association since 1992. He is an active member of the AIHA Real Time Detection Systems Technical Committee, and the AIHA Confined Spaces Committee. He is also a past chair of the Instrument Products Group of the International Safety Equipment Association. Robert has over 37 years of experience in the design, sale and marketing of atmospheric monitoring instruments used in confined space, industrial safety, and industrial hygiene monitoring applications.
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