A portable infrared heater that cannot be interlocked should be connected to which type of alarm?

For a portable infrared heater that cannot be interlocked, connecting it to a CO monitor alarm is crucial. Carbon monoxide (CO) is a colorless, odorless gas produced when fuels are burned, and it poses serious health risks such as poisoning or even death at elevated concentrations. Since infrared heaters often burn fuel to generate heat, potential CO levels could rise if combustion is incomplete or the exhaust is not properly vented.

In the context of a heater that lacks interlock features (which would otherwise prevent operation under unsafe conditions), a CO monitor becomes essential because it provides a safety mechanism to alert individuals when CO levels reach dangerous thresholds. This ensures that users can take appropriate action—such as ventilating the area or evacuating—if the heater malfunctions or if there are issues with exhaust.

Other options like a CO2 monitor alarm or an O2 monitor alarm do not directly address the key risks associated with fuel-burning appliances. CO2 monitors would be more relevant in scenarios where there is a risk of carbon dioxide buildup, typically in poorly ventilated spaces, but these situations are not the primary concern regarding heater operation. An O2 monitor would track oxygen levels, which might relate to combustion efficiency but is less critical than monitoring for CO build-up with