Chapter 04 · People & supply chainsHuman Rights & Social Sustainability

Confined space

Meaning statusEstablishedSource recordDirect document linkedWhy these are different

Definition

Under OSHA standards (29 CFR 1910.146 for general industry; 1926 Subpart AA for construction), a confined space is large enough for a worker to bodily enter and perform work, has limited or restricted means of entry or exit, and is not designed for continuous occupancy — tanks, silos, pits, manholes, tunnels and vessels. A confined space becomes permit-required if it may contain a hazardous atmosphere, engulfing material, a trapping configuration, or any other serious hazard.

References

OSHAConfined spaces overview

confined-space and permit-space definitions; examples

OSHA29 CFR 1910.146 Permit-required confined spaces

regulatory definitions and programme requirements

Overview

What it means

The classification triggers written permits, atmospheric testing, attendants, rescue planning and training before entry.

How it is used

Employers must identify confined spaces, assess hazards and run permit programmes; untrained would-be rescuers account for a large share of confined-space fatalities.

Why it matters

Confined-space incidents kill around a hundred US workers a year, most preventably — a core occupational safety and sustainability-reporting concern.

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Meaning status
Established
Verification date
Not recorded
Last updated
18 Aug 2026
What the classifications mean

Meaning status: Established

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