NEC Commercial Electrical Practice Test

What is the minimum size of the electrical flexible metal conduit (FMC) in inches?

1. 1/4 inch

2. 1/2 inch

3. 3/4 inch

4. 1 inch

The correct answer is: 1/2 inch

The minimum size of electrical flexible metal conduit (FMC) is 1/2 inch. This standard is established by the National Electrical Code (NEC) to ensure that the conduit can adequately protect electrical conductors while also providing sufficient strength and flexibility for installation. The 1/2 inch size is commonly used in various applications, accommodating conductors without excessive bulk, making it practical for many residential and commercial settings. Larger sizes of FMC are available and used for specific situations requiring more capacity or more robust conduit, while smaller sizes are not generally used in practice due to the necessity for physical protection and flexibility in the conduit system. Using a size smaller than the minimum can compromise the conduit’s ability to protect wiring and provide proper bending radius, which is essential for safe and effective electrical installations.