Which type of connection is NOT permitted for grounding electrode conductor connections?

The choice of using sheet metal screws for grounding electrode conductor connections is not permitted because these types of connections do not provide the reliable electrical continuity needed in grounding systems. Grounding electrode conductors must ensure a low-resistance path to ground to effectively mitigate electrical faults and enhance safety. Sheet metal screws can loosen over time due to vibration or thermal expansion, which can compromise the effectiveness of the grounding connection.

In contrast, listed clamps are specifically designed for this purpose, providing secure and durable connections. Similarly, wrapping conductors around nut and bolt connections or using soldered connections can also ensure a stable and compliant electrical connection. These methods typically provide a stronger, more reliable connection over time, which is crucial for grounding systems intended to protect against electrical hazards.