What does "notification appliance" refer to in a fire alarm system?

In a fire alarm system, the term "notification appliance" specifically refers to devices that are designed to alert occupants of a building to the presence of a fire or an emergency situation. These devices include horns, strobes, and speakers, which serve to provide audible and visual signals to effectively notify people within the environment that immediate action is required, such as evacuation.

The purpose of notification appliances is critical in ensuring occupant safety, as they are the primary means by which individuals are made aware of a fire threat. Efficient notification not only helps in reducing panic but also facilitates a timely evacuation, thereby minimizing risks associated with potential fire hazards. By employing multiple forms of notification such as sound (horns or alarms) and light (strobe lights), fire alarm systems accommodate individuals with varying sensory abilities and ensure a wider reach of alerting capabilities within the building.

In contrast, the other choices do not align with the definition of notification appliances. For instance, equipment that prevents fires or devices that control building electrical systems serve entirely different functions unrelated to occupant notification in emergencies. Likewise, while some systems have components for emergency communication, that is a separate category distinct from the notification appliances' role in alerting occupants.