top of page

Fire Alarm Identification


Fire alarms need to be suitable for any environment meaning there is a wide range of designs. When designing a fire alarm we look at the GRADE, CATAGORY and COVERAGE. An example of this would be a small office block that has fire alarm system that goes back to a control panel with battery back up that includes automatic fire detection in all areas of the building would be a Grade A L1 System


Fire alarms grades is the first step to designing a system, they are split into 6 grades;

A - A system that incorporates control and indication equipment, this system is installed to BS5839

B - Similar to grade A however not meeting the requirments in BS5839. This grade has actually been removed from the newest amendmant of BS5839 - 6.

C - Automatic detection and sounders connected to a common power supply with battery back up.

D - Mains powered with integrated battery back up.

E - Mains powered devices with no battery back up.

F - Battery powered systems.


The purpose of a catagory is to decide the purpose of the system, they are split into the following 3 options;

M - A system designed to be activated manually with no automated fire detection.

L - A system designed with the lives of people taking priority.

P - A system designed with the property taking priority.


The coverage is as it sounds, how much coverage of the property does the fire alarm provide, this is split into 5 option;

L1 - Automatic fire detection throughout.

L2 - Automatic fire detection installed in specific areas aswell as L3 requirments.

L3 - Automatic fire detection in escape routes and rooms that open onto them.

L4 - Automatic fire detection in escape routes, compromising areas and spaces like stairwells and corridors.

L5 - A system that is designed to protect a specific fire risk objective like a fuel storage area.

bottom of page