National Electrical Installation Standards

Standards as High as Your Own

Wednesday, June 22, 2022


Hello Code Friends!

Regarding CQD of Monday, May 23, 2022, about pan-head screws: There are two types of screws that look alike - pan-head and binder-head. For a long time, I wondered what was the difference. Binder-head screws are designed for electrical wiring. They have a ridge under the head, to keep wire from being squeezed out when the screw is tightened. The bottom of the head on pan-head screws is flat, so they are not good for electrical wiring. Whether they are code-compliant is a different matter.

See you at the NFPA conference.

Jeff Goldsmith, P.E.



Hi Jeff,

Always good to hear from you. We appreciate the follow-up information about screws with wire-binding capabilities. It's helpful for the CQD readers. Sheet metal screws are generally not compliant. Section 250.8(5) and (6) do specifically address thread forming machine screws and what is acceptable for connections of grounding and bonding conductors. Thanks again for the follow-up.

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