New York State Master Electrician Practice Exam

What is the required fire rating for a room housing service equipment totaling 1000KVA or larger?

1. One hour

2. Two hours

3. Three hours

4. Four hours

The correct answer is: Two hours

The required fire rating for a room housing service equipment totaling 1000 KVA or larger is two hours. This requirement is established to ensure that in the event of a fire, the integrity of the room is maintained long enough to prevent the fire from spreading and to protect the equipment as well as other areas of the building. A two-hour fire rating means that the room can withstand fire for at least that duration, which is critical for containing the flames and heat generated by electrical equipment that can malfunction or fail, particularly at high capacities like 1000 KVA. This rating is guided by codes and standards that prioritize safety and fire prevention in facilities housing significant electrical installations. Other options, such as one hour, three hours, and four hours, do not meet the specific requirements for this capacity of service equipment. A one-hour rating would be insufficient to protect against the potential hazards posed by such large electrical equipment, while three and four hours are stricter than necessary under current regulations for this specific application, emphasizing the balance between safety standards and practicality in construction codes.