The LWF Blog

Fire Safety Engineering for Design – Fire Detection & Alarm Systems – Part 169

February 5, 2024 11:56 am

LWF’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 168, LWF discussed the cabling used in fire alarm system installations. In part 169, we will talk about radio-based fire alarm systems/wireless fire alarm systems.

A radio-based fire alarm system or wireless fire alarm system is one where the components – detectors and control panel – can communicate with each other via radio signals rather than wiring.

There are certain advantages to a wireless fire alarm system:

  • The lack of a need for wiring means the systems can be installed quickly
  • The systems are less costly to install than a traditional wired alternative
  • Disruption from installation is minimal and can happen while the building is occupied
  • The system can cover more than one building without inter-building wiring
  • Damage to existing surfaces (walls etc) is minimal due to no wiring
  • Individual detectors can be identified on the system
  • Radio-based systems continue to operate in a fire situation (no need for fire-resistant cable)
  • They are ideal for temporary cover for special risks, events etc.

Of course, there are also disadvantages, as follows:

  • Each detector, call point or other device not wired will require a power source
  • The radiowave receiver may be affected by interference or the transmission path blocked
  • There are limitations on the allowed frequency spectrum which can lead to interference between simultaneous signals with older-style radio-based systems. (The issues potentially possible with older style radio-based alarm systems are not present in newer systems, due in the most part to the mobile phone industry which provides for radio devices to be in constant communication with the fire alarm control panel).

BS 5839-1:2017 – Fire detection and fire alarm systems for buildings – Code of practice for design, installation, commissioning and maintenance of systems in non-domestic premises gives compliance recommendations in section 27 for wireless fire alarm systems.

In part 170 of LWF’s series on fire engineering we will discuss power supplies for fire alarm systems. 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.

 

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