Final answer:
The minimum height for 480 Volt tunnel lighting above grade is not provided in the referenced material. It is dictated by local building codes or safety standards like the NEC or OSHA, which consider factors such as safety and type of area.
Step-by-step explanation:
The question regarding the minimum height above grade for 480 Volt tunnel lighting does not have a provided answer in the referenced material. This is typically a matter determined by local building codes or industry safety standards, such as those provided by the National Electrical Code (NEC) or the Occupational Safety and Health Administration (OSHA). Therefore, to determine the exact requirement, one would need to consult the applicable safety regulations or building codes for the specific location where the tunnel lighting will be installed.
To ensure safety and prevent electrical hazards, installations like tunnel lighting at high voltages, such as 480 Volts, are required to be placed at a certain height to protect personnel and the public from potential electric shock or related injuries. The minimum height requirement can be affected by factors such as the type of area (industrial, commercial, pedestrian), accessibility, and the purpose of the lighting.