What safety feature is required for gas fired heating appliances to manage the gas flow during a pilot outage?

The necessity for a shutoff device in gas-fired heating appliances is crucial for safety management during a pilot outage. A shutoff device is designed to automatically stop the flow of gas when it detects that the pilot light has extinguished. This feature is critical in preventing gas from leaking into the environment, which could lead to hazardous situations such as explosions or fires.

In contrast, automatic ignition is primarily used to light the burner without a pilot light, which doesn't address the issue of preventing gas flow in case of a pilot outage. A pressure relief system is focused on managing excess pressure within the appliance but does not deal directly with gas flow control during pilot outages. An emergency shutoff switch allows manual intervention in emergency situations but does not automatically respond to a loss of pilot light, lacking the immediate function necessary to cut off gas flow during such an event. Thus, the shutoff device is the appropriate safety feature to manage gas flow effectively during a pilot outage.