Silos, storage tanks, vessels, pumps and pipelines are a few examples of confined spaces in industry. Confined spaces may appear to be safe but can contain invisible hazards such as dangerous fumes, vapors, or insufficient oxygen.
OSHA General Industry Standard 1910.146(c)(2) If the workplace contains permit spaces, the employer shall inform exposed employees, by posting danger signs or by any other equally effective means, of the existence and location of and the danger posed by the permit spaces. NOTE: A sign reading DANGER -- PERMIT-REQUIRED CONFINED SPACE, DO NOT ENTER or using other similar language would satisfy the requirement for a sign.
- Never enter a confined space unless you have the proper training, equipment, and procedures!
- Determine if confined spaces have a potentially hazardous atmosphere before entering by using special air testing equipment.
Never assume that an open top pit is safe to enter, even if it is not labeled as a confined space. Pits, man-holes, sewer tunnels and tanks under construction could still pose dangers.
Permit-required confined spaces are confined spaces that have any hazard such as:
- hazardous atmosphere - such as low oxygen or a toxic gas
- potential for engulfment or suffocation - a risk of drowning or being buried
- a layout that might trap a worker through converging walls or a sloped floor
- or any other serious safety or health hazard
Permit-required confined spaces require workers to take safety measures such as rescue equipment to safely remove someone out of a confined space without entering.