Before entering a confined space, which hazards should be mitigated?

• A. Oxygen deficiency and hazardous gases
• B. Weather exposure and sunlight
• C. Tool ownership and maintenance
• D. Electrical grounding

Answer: (A)

In a confined space, the most critical factor is the air inside. Oxygen deficiency can cause fainting and death, and the presence of hazardous gases (toxic or flammable) creates immediate health and explosion risks. Because these atmospheric hazards can develop or linger inside a confined space, they must be tested and controlled before entry—ventilating to restore safe oxygen levels and remove or dilute dangerous gases, or applying other approved controls. Only when the atmosphere is confirmed safe should entry proceed with proper permits and rescue readiness.

Other issues like weather exposure, sunlight, tool ownership and maintenance, or electrical grounding matter in safety planning, but they do not determine whether it’s safe to breathe inside the space. The air quality is the primary concern to mitigate first.