Confined Space Safety: OSHA's Permit-Required Confined Space Standard

Confined Space Safety: OSHA's Permit-Required Confined Space Standard

Confined spaces are among the most dangerous work environments in the United States. OSHA's Permit-Required Confined Space standard has saved countless lives since its introduction, but confined space fatalities continue to occur — often because would-be rescuers enter without proper equipment and training.

What Is a Confined Space?

OSHA defines a confined space as a space that:

• Is large enough for a worker to enter and perform work
• Has limited or restricted means of entry or exit
• Is not designed for continuous occupancy

Examples include tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, tunnels, equipment housings, ductwork, and pipelines.

Permit-Required Confined Spaces

A confined space becomes "permit-required" if it has one or more of the following characteristics:

• Contains or has the potential to contain a serious atmospheric hazard (toxic, flammable, or oxygen-deficient/enriched atmosphere)
• Contains material that could engulf an entrant
• Has an internal configuration that could trap or asphyxiate an entrant
• Contains any other recognized serious safety or health hazard

The Permit System

Before any worker enters a permit-required confined space, a written entry permit must be completed. The permit documents:

• The space to be entered and the purpose of entry
• Authorized entrants, attendants, and entry supervisors
• Hazards of the space and measures to isolate and control them
• Acceptable entry conditions (atmospheric testing results)
• Rescue and emergency services available
• Communication procedures

Atmospheric Testing

Before entry and continuously during work, the atmosphere must be tested for:

• Oxygen content (acceptable range: 19.5% to 23.5%)
• Flammable gases and vapors (must be below 10% of LEL)
• Toxic air contaminants (must be below applicable PELs)

PPE for Confined Space Entry

Required PPE typically includes a full-body harness with retrieval line, respiratory protection (if atmospheric hazards are present), hard hat, and appropriate chemical-resistant clothing. RANOVA USA carries confined space entry equipment including harnesses, retrieval systems, and atmospheric monitors.