Horn strobes are used in conjunction with speaker strobes to grab the attention and warn people of pending smoke or fire. In a typical fire, smoke will reduce the light when the smoke thickens in the room causing one to start suffocating. Horn strobes are designed to be seen and detected amid smoke and fire to point people to the nearest exits.
A horn strobe is connected to the fire alarm panel and is designed to activate when a smoke detector or heat sensor detects the presence of smoke and fire. The sole purpose of a horn strobe in any fire alarm system is to alert people of the emergency and assist them it exiting the building as quickly as possible. It can provide necessary lighting to assist in search and rescue operations. The national fire code states that all commercial or industrial fire alarm systems must have one of more horn strobes to be in compliance.