Asphyxiant gases can be which type?

• A. Toxic inhalation hazards
• B. Flammable gases
• C. Simple asphyxiants
• D. Irritant gases

Answer: (C)

Asphyxiant gases cause suffocation by reducing the oxygen available in the air. They fall into two groups: simple asphyxiants and chemical asphyxiants. Simple asphyxiants don’t poison tissues directly; they dilute or displace oxygen in the surroundings, leading to hypoxia even though the gas itself isn’t toxic at exposure levels. That makes this the best classification for asphyxiant gases. Examples include nitrogen, argon, helium, and carbon dioxide at high concentrations. They aren’t inherently toxic, irritant, or related to flammability in the way those other hazard types are, which is why they’re described as simple asphyxiants. (Some gases can act as chemical asphyxiants by interfering with oxygen utilization, but that’s a different category.)