Which personal equipment is essential when working on 240v equipment where the available fault current is unknown?

When working on 240v equipment, particularly where the available fault current is unknown, personal protective equipment (PPE) is crucial to ensure safety from electrical hazards. The correct choice includes a flame-resistant long sleeve shirt, flame-resistant pants, and safety glasses, which are essential for protecting against potential electrical fires and impacts from arcs or flashes.

Flame-resistant clothing minimizes the risk of ignition from arc flash incidents, preventing burns, while safety glasses provide eye protection against debris or any possible sparks generated during electrical work. These elements are vital because the unknown fault current could lead to severe consequences, including electric shock or thermal burns.

The other options do provide some level of safety, but they do not adequately cover the specific risks associated with electrical work at this voltage and unknown current levels. For instance, while hard hats and gloves are useful, they don't focus on the specific hazards presented by electrical arcs. Safety boots and ear protection, while important in general safety protocols, do not address the risks posed by electrical faults. Similarly, face shields and insulated tools are valuable, but without the comprehensive protection that flame-resistant clothing offers, workers may still be at significant risk if an arc flash incident occurs.