Gas PipingQuestion 259 of 360
Why is it important to know that propane (LP) vapor is heavier than air when installing gas piping and appliances?
a.Because propane rises and collects at the ceiling
b.Because a propane leak settles into low areas such as pits, basements, and floor level where it can accumulate
c.Because propane is lighter than air like natural gas
d.Because propane cannot leak
Explanation
Propane vapor is heavier than air, so a leak sinks and pools in low spots such as pits, floor drains, crawl spaces, and basements rather than dispersing upward. That is why LP appliances and detection are handled differently than natural gas, which is lighter than air and rises. Ventilation and leak-detection strategy must match the fuel's density.
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