Gas PipingQuestion 260 of 360
Compared with propane, how does natural gas behave if it leaks indoors?
a.It is heavier than air and sinks to the floor
b.It has the same density as air and does not move
c.It is lighter than air and tends to rise and collect near the ceiling
d.It turns to liquid at room temperature
Explanation
Natural gas (mostly methane) is lighter than air, so a leak tends to rise and collect near the ceiling and high points rather than the floor. This influences where leaks gather and how spaces should be ventilated, opposite to heavier-than-air propane. Knowing the fuel density guides safe venting, detector placement, and leak response.
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