In general, a “confined space” is an enclosed or partially enclosed space that:
• Is not primarily designed or intended for human occupancy.
• Has a restricted entrance or exit by way of location, size, or means.
• Can represent a risk for the health and safety of anyone who enters, because of its design, construction, location, or atmosphere; the materials or substances in it; work activities being carried out in it; or the mechanical, process, and safety hazards present.
All hazards found in a regular workspace can also be found in a confined space. However, they can be even
more hazardous in a confined space than in a regular worksite. Hazards in confined spaces can include poor air quality, fire hazard, noise, moving parts of equipment, temperature extremes, poor visibility, and barrier failure resulting in a flood or release of free-flowing solid.
A “permit-required confined space” is a confined space that has specific health and safety hazards associated with
it. Permit-required confined spaces require assessment of procedures in compliance with Occupational Safety and Health Administration (OSHA) standards prior to entry.
Sources: Electric Motors and Control Systems-Frank D. Petruzella
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