What is the danger of gas appliance backdrafting?

Backdrafting occurs when combustion gases from gas appliances, such as furnaces or water heaters, are drawn back into the living space instead of being vented outside as intended. This situation poses significant safety risks because these combustion gases often contain carbon monoxide and other harmful pollutants. When backdrafting occurs, occupants can be exposed to these dangerous gases, which can lead to serious health issues or even fatalities.

Understanding the mechanics of proper ventilation is crucial for preventing backdrafting. Appliances are designed to operate with a balanced airflow; any disruption can lead to dangerous gases not being expelled.

In contrast to the other options, which either describe outcomes that do not generally happen as a result of backdrafting or suggest benefits that conflict with safety protocols. For instance, backdrafting does not improve appliance efficiency; rather, it indicates a failure in the exhaust system and can compromise both the performance of the gas appliances and the safety of the occupants.