In conduit guidelines, which length could represent the maximum allowed run for installed flexible metal conduit?

• A. 3 meters / 10 feet
• B. 9 meters / 30 feet
• C. 12 meters / 40 feet
• D. 6 meters / 20 feet

Answer: (D)

Flexible metal conduit has a defined maximum run length to protect the integrity of the installation, limiting how long a straight, unbroken FMC section can be between supports or terminations. This ceiling on length helps prevent excessive bending, mechanical damage, and strain on connections.

Among the options, the longest length shown—6 meters (20 feet)—fits that maximum allowance. Shorter lengths are still acceptable, but they don’t represent the limit you’re allowed to exceed; they’re simply within the permissible range. In practice, you’d also consider bends, fittings, and support spacing, and you’d route or reinforce the run if you need to cover a greater distance.