New York State Master Electrician Practice Exam

What is the minimum thickness required for a transformer vault floor made with bricks?

1. 4 inches

2. 6 inches

3. 8 inches

4. 10 inches

The correct answer is: 6 inches

The minimum thickness required for a transformer vault floor made with bricks is established to ensure adequate structural integrity and safety for the equipment it houses. A thickness of 6 inches is generally stipulated because it provides sufficient load-bearing capacity to handle the weight of the transformer and any associated equipment. This thickness also contributes to fire resistance, which is crucial in a transformer vault where hazardous materials may be present and where heat buildup could be a concern. More substantial thicknesses, such as 8 or 10 inches, would be more than what is typically required for standard applications, potentially adding unnecessary weight and cost without significant benefit. Conversely, a floor thickness of 4 inches may not provide the necessary strength and fire resistance needed for secure operation under the anticipated loads.