Why is propane heavier than air important for leak response?

• A. It can pool near floors and manhole covers; respond by ventilating from below, keeping ignition sources away, and evacuating if necessary.
• B. It rises to the ceiling and dissipates quickly.
• C. It is heavier than air outdoors only.
• D. It has no impact on indoor safety.

Answer: (A)

Propane is heavier than air, so if a leak occurs it tends to settle in low spots—near the floor, along walls, around doors and openings, or by manhole covers and in basements. This means danger can build up close to where people are, even if the leak isn’t obvious. The safest response emphasizes moving air at floor level to dilute and remove the gas, which is why ventilating from below is prioritized. At the same time, propane can ignite if a spark or flame is present, so keeping ignition sources away is essential. If the gas concentration could reach a hazardous level or if safe ventilation isn’t possible, evacuate and seek help.