Metal faceplates for devices shall be of ferrous metal not less than ___ inches in thickness.

Metal faceplates for devices shall be of ferrous metal not less than ___ inches in thickness.

• A. 0.300
• B. 0.003
• C. 0.030
• D. 0.150

Answer: (C)

Minimum thickness for metal faceplates made of ferrous metal is chosen to give a solid, non‑flexing mounting surface for devices and to keep screw holes and alignment stable during installation and use. A thickness of 0.030 inches (about 0.76 mm) provides enough rigidity to resist bending or denting while not being overly bulky or difficult to bolt on. The other options are impractical: 0.003 inches would be too flimsy and prone to damage; 0.150 or 0.300 inches would be unnecessarily thick and cumbersome to install. So 0.030 inches is the standard minimum that ensures durability and proper fit.

Minimum thickness for metal faceplates made of ferrous metal is chosen to give a solid, non‑flexing mounting surface for devices and to keep screw holes and alignment stable during installation and use. A thickness of 0.030 inches (about 0.76 mm) provides enough rigidity to resist bending or denting while not being overly bulky or difficult to bolt on. The other options are impractical: 0.003 inches would be too flimsy and prone to damage; 0.150 or 0.300 inches would be unnecessarily thick and cumbersome to install. So 0.030 inches is the standard minimum that ensures durability and proper fit.