At what elevation must an ignition source be located in a garage?

In garages, the ignition sources are typically required to be located at least 18 inches above the floor level to mitigate the risk of igniting flammable vapors, such as those from gasoline and other fuels that may accumulate near the ground. The reason for this specific height is based on the understanding that heavier-than-air vapors can settle close to the floor, increasing the risk of ignition if an electrical device or other ignition sources are placed too low.

Positioning devices such as electrical outlets, light fixtures, and heating equipment at this height helps ensure that they are above the level where these hazardous vapors might be present. This is a critical safety measure intended to minimize the risk of fire hazards in environments where flammable materials are commonly used or stored. Thus, the requirement to maintain an 18-inch elevation for ignition sources serves as an important guideline to enhance safety in garages and similar spaces.