In hazardous locations, how high must the ignition source of fuel-gas appliances be elevated above the floor?

• A. 12 inches
• B. 18 inches
• C. 24 inches
• D. 36 inches

Answer: (B)

In hazardous locations, fuel-gas appliances must have their ignition sources elevated to a height of 18 inches above the floor. This elevation is crucial as it helps minimize the risk of ignition in areas where potential gas leaks may occur. By positioning the ignition source higher, it reduces the likelihood of encountering combustible gases, which typically tend to accumulate close to the floor due to their density being less than that of air.

This requirement is particularly important in environments where flammable vapors or gases are present. Ensuring the ignition source is raised above this specified height not only aligns with safety codes and standards but also promotes a safer operation of appliances in residential spaces that might be vulnerable to gas accumulation.

The other choices do not meet the established safety guidelines for hazardous locations, as these either do not provide adequate elevation or exceed the typical requirements, making 18 inches the most appropriate and widely accepted standard for this setting.