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.