What hazards are associated with gases heavier than air?

• A. They dissipate quickly into the atmosphere
• B. They can cause electric shocks
• C. They accumulate in low areas and pose exposure risks
• D. They are highly flammable in open air

Answer: (C)

Gases heavier than air pose a significant risk because they do not dissipate quickly into the atmosphere like lighter gases. Instead, they tend to settle in low-lying areas, such as basements, pits, or other enclosed spaces. This accumulation can create hazardous conditions, leading to potential exposure to toxic gases or oxygen-deficient environments for anyone present in those areas. Understanding this behavior is crucial for emergency responders and workers in potentially hazardous environments, as it helps them anticipate where harmful concentrations of gases may occur and take appropriate safety measures.

The other options reflect characteristics that do not accurately describe the behavior of heavier-than-air gases. For example, gases that are lighter than air dissipate rapidly, making the first option misleading. The second option related to electric shocks is more relevant to specific types of materials rather than gases in general. The last option regarding flammability in open air does not apply universally, as not all heavier-than-air gases are highly flammable.