Fire Practice, HABM – June 2015

Fires on construction sites are always a danger to life and loss of physical assets. Often, a fire can rage undetected for a considerable time, by which time it has developed into something serious. Here, Paul Henson, Sales & Marketing Director at Ramtech Electronics, looks at why having an EN54 compliant wireless fire alarm system provides the best way forward.

Construction sites often have little or no technology-based fire protection system in place, which means that they rely on the people present seeing the fire and then alerting others, for example, by ringing a bell. This can present a number of issues as personnel on higher floors may not necessarily hear the alarm.

On larger construction sites, these variables and risks are multiplied several-fold, so that you end up with a situation where personnel and assets, plus adjacent buildings and their occupants, are all vulnerable exposed to fire.

Set against this background is the fact that fires on construction sites are far more frequent than most people realise. For instance, Zurich Insurance estimates that there are around 104,000 fires each year on site, costing around £400m. The Home Office has stated that around 40% of all fires on site are caused by arson.

Technology-based fire safety
Consider the scenario where a fire starts on site. Once workers become aware, a process that can take a critical amount of time, they immediately evacuate the area to a safe muster point. What would happen if, in the confusion, the alarm – which could simply mean someone ringing the bell – is not audible to everyone present? In the vital minutes before everyone became aware, the fire could have spread and seriously limited their escape routes.

A wireless fire alarm system overcomes these issues because it comprises manual fire alarm call points that are installed on site in accordance with the project’s Fire Plan. These call points are designed so that the system is interlinked, which means that all floors receive the same audible and visual alert signal even if the fire is contained to just one of them. This creates a completely secure mesh network, and alarms can be manually triggered by personnel from any call point. Where heat or smoke detectors are incorporated into the system, it provides automatic cover 24/7, ensuring that the site is protected even when personnel are not present.

At the same time, the base station allows fire officers to instantly identify which fire point or heat/smoke detection unit has been activated, allowing emergency services to be deployed to the exact source. Modern wireless fire alarm systems are able to provide this site wide coverage, whether it’s a multi-use redevelopment project or a large and complex concrete, steel and timber frame building – the wireless frequency passes through all solid materials found on site.

Regulatory requirements
However, not all wireless emergency systems are the same – they must have been independently tested and approved to comply with EN54 and therefore with the new Construction Products Regulation (CPR).

CPR requires that where a harmonised technical standard exists for a product it must comply with the provisions of that standard. EN54 is the harmonised standard relating to fire detection and fire alarm systems.

In essence, the CPR states that fire safety products must be CE marked with a Declaration of Performance (DoP) and to obtain this it must be tested by an approved external agency, known as a notified body. If the fire alarm system you are thinking of specifying for a construction site has been tested by a notified body you’ll see a four digit test centre number after the CE mark. To be absolutely sure, ask your supplier for their DoP certificate. If the certificate you are presented simply covers, for example, an individual component within a larger unit, it does not follow that the whole unit meets EN54 requirements.

To comply with EN54, the complete unit – and every unit in the system including the base station, fire call point or smoke and heat detection unit – should all have been tested to the relevant part of EN54. If in doubt, read the Declaration of Performance to see what has been tested.

Conclusion
The principal benefit of using a wireless fire alarm system compared to a wired version is that it avoids the need for specialist trades on site. That makes placing the fire alarm call points, active heat detectors and smoke detectors a simple process – there is no need for wires or specialist trades to help with installation. As the site progresses, that means the wireless units can be quickly repositioned, and are equally suitable for demolition or refurbishment projects. Other features such as a three-year battery life on some wireless systems all add to their usability.

The need for wireless fire alarm systems is likely to grow, especially with the move to timber frames buildings and high rise developments to make optimum use of available land. Both these present their own specific dangers from fire and we are seeing more clients take proactive steps to ensure that their appointed contractor uses a fire alarm system that is fully compliant with EN54 requirements.”

This article was published in HABM, June 2015

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