What is prohibited in areas containing sleeping quarters?

In areas containing sleeping quarters, nonrecirculating direct-fired industrial air heaters are prohibited primarily due to safety concerns related to air quality and the potential for combustion byproducts. These heaters operate by directly burning fuel, which can introduce harmful gases such as carbon monoxide and nitrogen dioxide into the living space if there is inadequate ventilation.

In contrast, the other options typically have established guidelines or safety standards that allow their use in facilities with sleeping quarters, as they either do not produce harmful emissions or are designed to minimize risks associated with combustion. For instance, electric heaters do not pose the same risks since they do not depend on combustion for heat, and indirect-fired heaters are designed to exhaust combustion products outside the living area. Gas meters are also not a direct hazard to occupants as they are simply measurement devices.

Overall, the prohibition of nonrecirculating direct-fired industrial air heaters in sleeping quarters is a precautionary measure to ensure the safety and well-being of the occupants.