Oklahoma Electrical Practice Exam

How high must an open fluorescent lighting fixture be set above the floor in a Class I commercial garage?

1. 10 feet

2. 11 feet

3. 12 feet

4. 13 feet

The correct answer is: 12 feet

In a Class I commercial garage, the open fluorescent lighting fixture must be set at a minimum height of 12 feet above the floor. This requirement is established to ensure safety and compliance with electrical codes, as Class I areas are defined as locations where flammable vapors are present. By positioning fixtures at this height, there is a reduced risk of the fixtures coming into contact with equipment or vehicles, which could lead to damage, fire hazards, or inadequate safety conditions. Additionally, higher installation helps avoid the accumulation of flammable vapors near the light source, minimizing potential ignition risks. Proper clearance is essential in these environments to maintain a safe workplace and to ensure that the lighting effectively illuminates the area without interference. Having the fixtures at the specified height also aids in maintenance and allows for a more uniform distribution of light across the garage space. This standard promotes both safety and functionality in commercial garages.