The LWF Blog
Fire Safety Engineering for Design – Fire Detection & Alarm Systems – Part 142
July 24, 2023 10:26 amLWF’s Fire Safety Engineering blog series is written for Architects, building designers and others in the construction industry to highlight and promote discussion on all topics around fire engineering. In part 141, LWF looked at category L fire detection and alarm systems in more detail. In part 142, we discuss supervising station fire alarms and manual fire alarms.
Supervising Station Fire Alarms
A supervising station fire alarm is most commonly found where an organisation occupies a group of buildings. The fire alarm coverage takes the form of networked systems, with one building (usually the main building) designated as the main control point for a large fire alarm system covering a number of buildings.
A college or university campus may use a supervising station fire alarm system, for example, and the main control panel would be found in a central building under the control of the site management team. Each building on campus would have an individual fire alarm system that is networked to the main control system.
These systems can be useful for the Fire Service when attending a fire on campus because they can establish an information point at a safe distance from the fire location.
This type of system is defined in NFPA 72, but is not mentioned specifically in BS 5839 (which is not to imply that supervising station fire alarms are not appropriate for use in territories using British Standards, just that each system would require approval from relevant bodies as usual).
Manual Fire Alarm Systems
A manual fire alarm system is one which comprises only manual call points placed at strategic locations. It would not include any automatic fire detection at all. If a fire were to start, it would rely on a person on site discovering the fire and using the manual call point to trigger the alarm.
Normally, it is necessary for any category L system (for life safety) to fulfil the requirements for category M systems. The NFPA does not identify this type of system.
The level of coverage necessary for a building must be determined by a suitably experienced designer, taking specialist advice when required.
A category M system might be found in a small place of employment, such as a small office or shop where the fire is most likely to be discovered by a building occupant. It would not be appropriate for a larger building with unoccupied spaces, or one in which there were sleeping quarters of any kind.
In part 143 of LWF’s series on fire engineering, we will talk about fire alarm systems for domestic dwellings. In the meantime, if you have any questions about this blog, or wish to discuss your own project with one of our fire engineers, please contact us.
Lawrence Webster Forrest has been working with their clients since 1986 to produce innovative and exciting building projects. If you would like further information on how LWF and fire strategies could assist you, please contact the LWF office on 0800 410 1130.
While care has been taken to ensure that information contained in LWF’s publications is true and correct at the time of publication, changes in circumstances after the time of publication may impact on the accuracy of this information.