What type of materials is prohibited when working near energized equipment?

When working near energized equipment, it is crucial to avoid materials that can easily catch fire or melt under heat. The correct answer includes acetone, nylon, polyester, and rayon, all of which are synthetic materials. These materials can ignite and burn rapidly in the presence of electrical arcs or other sources of heat, posing a significant safety hazard.

In contrast, leather and cotton, while not entirely free from risk, tend to have more desirable properties in an electrical safety context because they do not melt and drip like synthetics do. Wool and rubber can provide some insulation, with rubber often used as electrical protective gear, reflecting their relative safety. Denim and canvas also pose less risk compared to synthetic alternatives as they are generally made from natural fibers that are less flammable. Thus, the selection of materials for working near energized equipment requires careful consideration to prioritize safety, making the options that include synthetic materials particularly problematic.