Which scenario is an atmospheric hazard?

• A. Bright daylight in open air
• B. Fresh air in a well-ventilated space
• C. No odor
• D. Oxygen enrichment

Answer: (D)

Atmospheric hazards are dangers tied to the air you’re breathing rather than the objects around you. Oxygen enrichment creates an atmosphere with higher-than-normal oxygen levels, which increases flammability and can cause oxygen toxicity, making it a true atmospheric hazard. Bright daylight in open air and fresh air in a well-ventilated space are normal, non-hazardous conditions, and while some hazards are odorless, the explicit hazard described here is the elevated oxygen level that alters the air itself.