To ensure electrical continuity in structural steel used for lightning protection, what must be avoided?

For ensuring electrical continuity in structural steel used for lightning protection, it is crucial to avoid any materials or conditions that can hinder the flow of electricity. Insulation, dirt and grime, and paint can all serve as barriers that disrupt electrical connectivity.

Insulation, such as coatings or wraps that are not intended for grounding, can prevent electric current from traveling freely along the steel structure. This is particularly important in lightning protection systems, where the goal is to provide a low-resistance path for lightning strikes.

Dirt and grime accumulate over time and can create resistance at the contact points between steel structures. This reduces the effectiveness of the grounding system and can lead to potential lightning strikes not being properly conducted away from the building.

Paint serves a similar function as insulation when it comes to electrical connections. It can prevent metal surfaces from making adequate contact, thus inhibiting the essential electrical continuity required for a reliable lightning protection system.

Thus, to maintain effective electrical continuity and ensure optimal lightning protection, it is paramount to avoid insulation, dirt, grime, and paint on structural steel components involved in the lightning protection measures.