Fixtures & Water HeatersQuestion 70 of 120
The same gas water heater is installed in that garage on a concrete slab. What is the minimum height that the source of ignition must be elevated above the garage floor?
a.18 inches
b.12 inches
c.24 inches
d.6 inches
Explanation
Ignition sources in a garage must be at least 18 inches above the floor because gasoline vapors are heavier than air and pool at floor level. 12 inches and 6 inches leave the burner inside the vapor layer. 24 inches is higher than required and is not the code figure, although a taller platform would still comply.
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