What is the minimum contact area for a bonding plate for ground connections on a steel frame building?

The minimum contact area for a bonding plate used in ground connections on a steel frame building is specified as 8 square inches. This requirement ensures that there is adequate surface area for electrical bonding, which is crucial for the effective dissipation of electrical energy during a lightning strike or fault condition.

The larger surface area of the bonding plate improves the contact quality between the plate and the steel structure, reducing resistance. Proper bonding helps to maintain uniform potential throughout the frame, preventing dangerous voltage differentials that could pose a hazard to both equipment and personnel.

The specification of a minimum of 8 square inches is grounded in industry standards, which aim to provide a reliable level of safety and performance in grounding systems. Ensuring that grounding connections comply with these minimum specifications is essential for the safety and effectiveness of a lightning protection system.