Are bonding connections for metal parts of signs and outline lighting systems permitted to be made using sheet metal screws?

Bonding connections for metal parts of signs and outline lighting systems are critical for ensuring electrical safety and preventing voltage build-up that could lead to electrical shock or fire. The use of sheet metal screws for these connections is not permitted because they do not provide the reliable electrical continuity required for bonding.

For bonding, connections must be robust and able to withstand environmental factors, mechanical stress, and potential corrosion over time. Screws may not ensure a strong and conductive connection because they can loosen or corrode, compromising the effectiveness of the bond. Electrical code standards typically specify that bonding connections should be made using methods that guarantee a lasting electrical connection, which are not provided by sheet metal screws.

Secure, effective bonding is vital for the safety of electrical systems, ensuring that any fault currents have a low-resistance path to ground, thus minimizing risk. Therefore, the standards dictate that bonding should be done using methods or materials designed expressly for that purpose, which do not include sheet metal screws.