The answer to these questions should be simple: if you own or manage a commercial or industrial property, the manner in which your fire system has been installed should comply with section 4 of BS 5839-1:2017 — the British Standard for fire detection and fire alarm systems in non-domestic premises. Unfortunately, not all fire alarm installation companies work with—or even own a copy of—the British Standard. And although a fire detection and fire alarm system should be installed to section 4 of BS 5839-1, this isn’t always the case.
Perhaps the most noticeable detail of a fire detection and fire alarm system installation is the method of cable support. An inadequate cable support system is also one of the most common non-compliances we see day to day.
What are some acceptable methods of cable support?
• Cable clips are often used to fix the cables directly to the fabric of the building, such as to a concrete wall or ceiling.
• Conduit and trunking are used to provide some protection or to segregate the fire cables from other services. Conduit and trunking can be plastic or galvanised.
• Cable tray is a containment system used to segregate from other services and to support cables, usually above suspended ceilings or in factory settings.
However, not all clips, conduit fixings or cable trays are created equally. BS 5839-1:2017 26.2f) states: “Methods of cable support should be non-combustable and such that circuit integrity is not reduced below that afforded by the cable used, and should withstand a similar temperature and duration to that of the cable, while maintaining adequate support.”
Did you know: standard fire resistant cable should be able to survive for up to 30 minutes in a fire condition. Therefore, according to the British Standard, the cable support system should also be able to withstand up to 30 minutes in a fire condition. There are two main reasons behind this: firstly, to ensure the fire system continues to operate in the event of a fire or a fault condition. If the fixings fail due to fire or perhaps human error, the weight of the cable could cause disconnection from a device or from the control panel. This would be considered a major non-compliance. The second reason is explained by BS 5839-1:2017 26.2f) note 11: “experience has shown that collapse of cables, supported only by plastic cable trunking, can create a serious hazard for firefighters, who could become entangled in the cables.”
The photo above shows unsupported fire cables next to a new cable tray system, installed by Porton Fire Services Ltd during an ongoing installation project. The existing cables are laid across the ceiling grid of this office area and secured with plastic cable ties. If a fire were to occur, the plastic ties could perish. This would leave the cables with a very high probability of collapsing, thus endangering the lives of occupants attempting to evacuate and firefighters attempting to quell the flames.
Is any part of your fire system wholly supported by plastic fixings, or perhaps unsupported at all? If so, it could be non-compliant.
From this information, the question arises: when choosing a fire company, how do you ensure they know what they’re doing? This is where third-party certification comes in. Third-party certification is a way for companies to prove their competence by undergoing regular audits from an unbiased third-party. We at Porton Fire Services Ltd are proudly certified by the Security Systems and Alarms Inspection Board (SSAIB).
However, one major problem within the fire industry is that third-party certification is seen as a mark of distinction instead of a requirement. This means that not all fire detection and fire alarm system installation companies are monitored for compliance with current standards nor is their competence verified, which could lead to major problems for you down the road.
We at Porton Fire Services Ltd guarantee our installation work complies with BS 5839-1:2017. If you suspect your fire detection and fire alarm system may have areas of non-compliance, please contact us to arrange a free site survey.