We often use the term “Confined Space” loosely to also include “Permit-Required Confined Space” but the difference is that one space is regulated by OSHA and the other is not, one of the spaces has a hazard(s) associated with it and the other does not. The OSHA standard 1910.146 (c)(1) requires that employers evaluate the workplace, meaning the buildings, grounds, equipment or materials, to determine if any of those spaces meet the definition of a PERMIT-REQUIRED CONFINED SPACE. In order for any space to meet this criteria, it must first meet the 3 elements of a CONFINED SPACE.
Many workplaces contain spaces that are considered “CONFINED SPACES” because their configuration meets the following criteria: 1. The space is large enough and so configured that an employee can bodily enter and performed assigned work; 2. Has limited or restricted means of entry or exit; AND 3. Is not designed for continuous occupancy. All three of the criteria must be met; if any part is missing, the space does not meet OSHA’s definition of a confined space and can never be considered a permit-required confined space. For instance, if an entry point is a side-hinged door that we simply open and walk through, it is not considered to be a limited or restricted entry. If the entry requires us to stoop or crawl, the entry is considered restricted.
Permit-Required Confined Spaces are spaces that meet the CONFINED SPACE criteria but contains or have the potential to contain: 1. A hazardous atmosphere; 2. An engulfment hazard; 3. An internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or a floor which slopes downward and tapers to a smaller cross-section; OR 4. Contains any other recognized serious safety or health hazards.
- Hazardous atmospheres contain OR have the potential to contain:
- Flammable gas, mist or vapor in excess of 10% of it’s Lower Flammability Limit (LFL);
- Airborne dust that meets or exceeds its concentration of its LFL;
- Oxygen <19.5% or >23.5%;
- Atmospheric concentrations of substances above PEL; OR
- IDLH atmospheric conditions.