Confined Spaces
Date Posted: 02/10/2024
Confined spaces, such as utility holes, crawl spaces, and tanks, are not designed for continuous occupancy and are difficult to exit in an emergency. People working in confined spaces face life-threatening hazards, including toxic atmospheres/substances, electrocutions, explosions, and asphyxiation. Based on findings from the Bureau of Labor Statistics (BLS), from 2011 to 2018, 1,030 workers died from occupational injuries involving a confined space. The annual figures range from a low of 88 in 2012 to a high of 166 in 2017. It is also important to note that 60% of all confined space fatalities are people who enter the space intending to rescue another worker.
What is a Confined Space?
A space large enough and so configured that an employee can fully enter and perform assigned work has limited or restricted means for entry/exit, and it is not designed for continuous human occupancy.
What is a Permit-Required Confined Space?
According to WAC 296-809-099, "permit-required confined space" (permit space) to describe a confined space that has one or more of the following characteristics capable of causing death or serious physical harm:
Contains or has the potential to contain a hazardous atmosphere.
Contains a material with the potential to engulf someone who enters.
Has an internal configuration that could allow someone entering to be trapped or asphyxiated by inwardly converging walls or by a floor, which slopes downward and tapers to a smaller cross-section.
Contains any physical hazard. This includes any recognized health or safety hazards, including engulfment in solid or liquid material, electrical shock, or moving parts.
Contains any other recognized serious safety or health hazard that could either:
Impair the ability to self-rescue.
Result in a situation that presents an immediate danger to life or health.
Note: Only enter a confined space if authorized and trained.
Atmospheric Monitoring & Acceptable Entry Conditions
Atmospheric testing and monitoring are required to confirm acceptable entry conditions into any confined space. The confined space must be tested before entry, and acceptable entry conditions must be achieved and maintained during entry (WAC 296-809-50012). Atmospheric monitoring will be accomplished using a calibrated and tested direct reading instrument.
Atmospheric testing equipment shall test for hazards in the following order:
Oxygen
Combustible gases and vapors
Toxic gases and vapors
Acceptable entry conditions (WAC 296-809-099) are the conditions that must exist in a permit-required confined space to allow safe entry and work. Acceptable entry conditions include:
Oxygen levels within the acceptable range (19.5%-23.5%).
Flammable range, including gas, vapor, or mist concentration, is less than 10% of the lower flammable limit (LFL/LEL).
Ensure combustible dust hazards are not present.
Substances with a Permissible Exposure Limit (PEL) or ACGIH Threshold Limit Value (TLV) that cause acute illness or impair the entrant's ability to self-rescue will be controlled to remain below the limits.
All electrical, mechanical, and other kinetic hazards within the space capable of causing death or serious physical harm must be de-energized, locked, and tagged out (LOTO).
Engulfment or entrapment hazards shall be eliminated or controlled.
Permit-Required Confined Space Rescue
Adequate rescue services should be available during permit-required confined space operations (WAC 296-809-50014). There are two primary types of rescue for confined spaces. Entry and non-entry rescue. Non-entry rescue should be utilized whenever possible.
Non-Entry Rescue: Retrieval systems should be used as a primary means of rescue when workers enter a permit space unless such equipment increases the overall risk of entry or when non-entry rescue is infeasible and entry rescue must be utilized. Retrieval systems must have a full-body harness and a retrieval line attached at the dorsal “D ring” near shoulder level or above the head. If harnesses are not feasible or would create a more significant hazard, wristlets may be used instead of the full-body harness. The retrieval line shall be firmly fastened outside the space so rescue can begin when retrieval becomes necessary. A mechanical device shall be available to retrieve personnel from vertical confined spaces more than five (5) feet deep.
Entry Rescue: A Permit Required Confined Space (PRCS) rescue team is required to be available even when non-entry rescue is feasible. The PRCS entry rescue team requires specialized knowledge and training to perform rescue operations. When selecting a rescue team or service for PRCS entry rescue, the following evaluations shall be completed:
An initial evaluation to determine whether a potential rescue service or team is adequately trained and equipped to perform permit space rescues needed at the facility and whether such rescuers can respond promptly.
A performance evaluation is conducted to determine if the planned rescue methods are adequate to ensure authorized entrants' timely and efficient rescue.
Duties & Responsibilities
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| All Employers |
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| Entry Employers |
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| Host Employers |
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