Which term describes equipment that is approved for use in flammable atmospheres?

The term that describes equipment approved for use in flammable atmospheres is intrinsically safe equipment. This type of equipment is designed to operate safely in environments where flammable gases, vapors, or dust may be present. The design limits the energy, both electrical and thermal, that could ignite hazardous materials, ensuring that even under fault conditions, the equipment remains safe.

Intrinsically safe equipment is rigorously tested and certified to meet specific standards, making it suitable for use in potentially explosive atmospheres, such as those commonly encountered in various industries such as oil and gas or chemical manufacturing. This equipment plays a critical role in maintaining safety and preventing accidents, particularly in hazardous locations where the risk of ignition must be minimized.

While terms like fire-retardant equipment and non-flammable equipment imply some measure of safety or resistance to fire, they do not address the specific electrical and thermal energy controls necessary for use in flammable atmospheres. Safe equipment is a more general term that does not necessarily convey the rigorous safety standards that intrinsically safe equipment adheres to.