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.