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.
Confined spaces are not designed for continuous occupancy and often have limited means of entry and exit. Even when they appear open or accessible, hazardous conditions can develop quickly and without warning.
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.
Hidden Hazards in Confined Spaces
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.
Confined spaces may contain hazardous atmospheres, including oxygen-deficient environments, toxic gases, or flammable vapors. These hazards are often not visible and cannot be detected without proper testing equipment.
Entry Requirements and Air Testing
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.
Air monitoring should be conducted before entry and continuously, when required, to ensure conditions remain safe for workers inside the space.
Permit-Required Confined Spaces
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
Safety Measures and Rescue Planning
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.
Rescue plans must be in place before entry begins, and workers should never rely on improvised rescue efforts. Proper equipment, trained personnel, and clear procedures are essential to safely respond to an emergency in a confined space.
.jpeg)
.jpg)