<P> A fire alarm system has a number of devices working together to detect and warn people through visual and audio appliances when smoke , fire , carbon monoxide or other emergencies are present . These alarms may be activated automatically from smoke detectors , and heat detectors or may also be activated via manual fire alarm activation devices such as manual call points or pull stations . Alarms can be either motorized bells or wall mountable sounders or horns . They can also be speaker strobes which sound an alarm , followed by a voice evacuation message which warns people inside the building not to use the elevators . Fire alarm sounders can be set to certain frequencies and different tones including low , medium and high , depending on the country and manufacturer of the device . Most fire alarm systems in Europe sound like a siren with alternating frequencies . Fire alarm electronic devices are known as horns in the United States and Canada , and can be either continuous or set to different codes such as Code 3 . Fire alarm warning devices can also be set to different volume levels . Fire Alarm systems in the United Kingdom are tested at a weekly basis in compliance with the BS - fire 2013 regulations . </P>
<P> A fire alarm system has a number of devices working together to detect and warn people through visual and audio appliances when smoke , fire , carbon monoxide or other emergencies are present . These alarms may be activated automatically from smoke detectors , and heat detectors or may also be activated via manual fire alarm activation devices such as manual call points or pull stations . Alarms can be either motorized bells or wall mountable sounders or horns . They can also be speaker strobes which sound an alarm , followed by a voice evacuation message which warns people inside the building not to use the elevators . Fire alarm sounders can be set to certain frequencies and different tones including low , medium and high , depending on the country and manufacturer of the device . Most fire alarm systems in Europe sound like a siren with alternating frequencies . Fire alarm electronic devices are known as horns in the United States and Canada , and can be either continuous or set to different codes such as Code 3 . Fire alarm warning devices can also be set to different volume levels . Fire Alarm systems in the United Kingdom are tested at a weekly basis in compliance with the BS - fire 2013 regulations . </P>
the primary role of a fire alarm system is to
the primary role of a fire alarm system is to
detect and warn people through visual and audio appliances when smoke , fire , carbon monoxide or other emergencies are present
detect and warn people through visual and audio appliances when smoke , fire , carbon monoxide or other emergencies are present