What is the minimum thickness of a steel plate used to protect cables laid in wood notches?

What is the minimum thickness of a steel plate used to protect cables laid in wood notches?

• A. 1/16 in
• B. 1/8 in
• C. 1/4 in
• D. 1/32 in

Answer: (A)

The main idea is protecting electrical conductors from damage caused by fasteners in wood members. When a cable is laid through a notch or bore in wood and is within 1-1/4 inches of the face, you must install a steel plate (nail plate) to shield the cable from nails or screws. The code sets the minimum thickness for these protective plates at 1/16 inch (0.0625 in). This thickness provides enough resistance to punctures while being practical to install. Thinner plates, like 1/32 inch, would offer less protection and could be penetrated more easily, while thicker plates (1/8 inch or 1/4 inch) meet or exceed the minimum but aren’t required unless specific conditions call for extra protection. The important takeaway is that 1/16 inch is the required minimum thickness to meet the protection requirement.

The main idea is protecting electrical conductors from damage caused by fasteners in wood members. When a cable is laid through a notch or bore in wood and is within 1-1/4 inches of the face, you must install a steel plate (nail plate) to shield the cable from nails or screws. The code sets the minimum thickness for these protective plates at 1/16 inch (0.0625 in). This thickness provides enough resistance to punctures while being practical to install. Thinner plates, like 1/32 inch, would offer less protection and could be penetrated more easily, while thicker plates (1/8 inch or 1/4 inch) meet or exceed the minimum but aren’t required unless specific conditions call for extra protection. The important takeaway is that 1/16 inch is the required minimum thickness to meet the protection requirement.