What is a hazardous atmosphere?
According to OSHA, a “hazardous atmosphere” is an atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue, injury, or acute illness from one or more of the following causes:
- Flammable gas, vapor, or mist in excess of 10 percent of its lower flammable limit (LFL)
- Airborne combustible dust at a concentration that meets or exceeds its LFL
Note: This concentration may be approximated as a condition in which the combustible dust obscures vision at a distance of 5 feet (1.52 meters) or less.
- Atmospheric oxygen concentration below 19.5% or above 23.5%
- Atmospheric concentration of any substance with an OSHA permissible exposure limit above the permissible exposure limit (PEL)
- Any other atmospheric condition that is immediately dangerous to life or health
More Q&As from our experts
- What is a permit required confined space (PRCS)?
- What combustible gases are associated with confined spaces?
- What are the most common toxic gases in confined spaces?