In Class III, Division 1 locations, how should nonincendive field wiring circuits be installed?

In Class III, Division 1 locations, nonincendive field wiring circuits are designed to prevent ignition of hazardous materials, which can include combustible fibers and flyings. The correct installation method involves using multiconductor cables within a grounded metal shield.

This installation ensures several key safety features. Firstly, the grounded metal shield provides a crucial layer of protection against electrical interference and potential fault currents that could spark and ignite hazardous materials. Grounding the shield helps to channel any fault currents safely to the ground, minimizing the risk of electrical discharge. Additionally, the use of multiconductor cables allows for more efficient wiring systems, with multiple conductors contained within a single shielded cable, which can also mitigate the risk of accidental contact with unshielded wiring.

Using only single conductor cables, unshielded cables, or cables with non-grounded shields would not offer the same level of protection. Single conductor cables could be more vulnerable to faults without the benefit of a shared ground shield. Unshielded cables lack any protective barrier against electrical interference and external hazards, increasing the risk of ignition in a hazardous environment. Non-grounded shields do not divert fault currents safely, which could lead to dangerous situations in the presence of combustible materials. Thus, the usage of multiconductor