Unfortunately, in the construction industry, not only is it not inconceivable for a tradesman to compromise the fire safety of a building, it is almost guaranteed that he, or she almost inevitably will.

Let us consider the situation of an electrician responding to a request from a customer to fit concealed downlighters into a ceiling. Assuming a reputable electrician is used, one would feel confident that the electrician would be adequately trained to provide an electrically safe installation, but compared to the motor mechanic, whose training would invariably encompass the important safety features in a vehicle, there is a serious risk that the electrician would not be aware of the other safety features in the building.

To some extent the lack of awareness of the safety features in a building may result from labelling and publicity. In the construction industry the responsible component manufacturer, in this case the downlighter producer, may put a warning on or in the box, but the guidance will rarely be specific as to what should be done, only a vague warning that the unit must be fitted in a manner that does not reduce the fire protection. Probably the worst type of packaging is that which declares the light has been tested without giving full details as to how and what features need to be incorporated in the installation. Such packaging places complete responsibility on the installing electrician to establish the way it was tested and what additional measures need to be employed to ensure that the fire separation is achieved. More worryingly it is left to the installer to establish what level of fire resistance is needed for the penetrated element, if it is to comply with Regulatory Guidance, or the declared Fire Strategy. This rarely features in any courses run for the electrical trades.

When a ceiling lining is critical it is possible to make it difficult to fit concealed lights by incorporating steel mesh, either above single layer plasterboard linings or between double layers of boards, not that there is any experience of this having been done. Whilst the special tools would only extend to metal cutters, hopefully encountering such a mesh might make the lighting fitter question why such a mesh exists. However, this cannot be taken for granted as the presence of a steel ‘RSJ’ immediately behind a plasterboard ceiling fails to stop some electricians from completing the task.

Throughout the UK, Building Regulations are functional, ie the design and construction must be fire safe with respect of the risk that the property and its use represents, but in all cases there are guidance documents published by Government that provide a prescriptive solution to the objectives. These take the form of Approved Documents in England & Wales and it was Approved Document P, implemented on 1 January 2005, that placed the responsibility onto the electrician to ensure that his/her fitting of lights and other electrical equipment, did not reduce the fire protection or separation levels. In respect of fire, the Approved Document is AD B and this has just undergone a major revision which went out for Public Consultation during the summer of 2005. This draft includes a new Annex G which requires a log book to be completed in which all items provided for the fire performance are readily identified, including their ratings and test evidence. Whilst this is not law it would, if adopted, give the electrician details of the fire ratings to be maintained which should, in the case of downlighters, identify the need to fit lighting covers/hoods/tents over the light to maintain the fire rating, or to use a correctly tested and rated light. Half of the battle is won, but he still has to select a properly tested component!

The annual examination of the building akin to the MOT test may not be far away either, although ironically this will be unlikely to impact on dwellings, where poorly selected and/or fitted lights could have the most serious consequences. In 2006 ongoing fire safety legislation changes so that commercial and public properties have to be regularly Risk Assessed for compliance with fire safety. This is unlikely to be annually but it must be at such a frequency that any changes in the building are evaluated for their impact on the fire safety requirements. Currently the Risk Assessors performing this function are a disparate group with mixed skills, but hopefully the industry, or possibly the courts will soon teach them what to look for in respect of protection for the structure needed to compensate for poorly fitted lights. These new millennium ‘fire bobbies’ may, if they do their job properly, keep the errant electrician out of court, or even prison, but they may also cause such electricians to return to site and fit improved lights or additional lighting protection at their own cost. With AD ‘P’ in existence they will not be able to claim that the protection was not specified - it is their job to recognise the need.

This brings us to the subject of selecting the correct product(s) for the job. There are no product standards, nor European Technical Approvals, nor bespoke fire test procedures for fire safe lights or lighting covers and there will not be for the foreseeable future. The electrician will have to become astute at differentiating between correctly tested and assured products because it is their responsibility. Modern building practice has meant that many floor constructions are now much less tolerant of exposure to fire because modern factory made composite joists have minimal inherent fire resistance. With solid timber joists of generous proportions they could withstand exposure to fire for approximately 20 minutes and exploitation of one cavity would not have an impact on adjacent cavities. With many modern joists having an inherent fire resistance measured in minutes and others permitting rapid fire spread from cavity to cavity this is no longer the case.

The protection to a floor cavity provided by a ceiling that incorporates a downlighter is governed by the interaction between the light, the ceiling materials and construction and any protection provided. A light, protected by a lighting hood/tent/cover, or which embodies its own fire protection, will not afford the same level of protection when installed in wallboard as it would in Soundbloc/Soundshield two very visually similar products, let alone in fire performance enhanced boards such as, Fireline, Fireshield or Glasroc. Two layers of plasterboard often impart three times the level of protection to a floor than a single layer. As a consequence, a one hour result of a concealed light in a two layer board does not translate into a 30 minute result in a single layer board, especially if the single layer is only of ‘wallboard’ quality. A component tested in a 15mm lining cannot be used with a 12mm lining, unless a Field of Application Report or a Test Report from an acknowledged fire authority demonstrates that it is safe.

Caveat Emptor (buyer beware) has been an established purchasing rule for a long time, but in the case of selecting downlighters, or downlighter protection, rarely has it carried such a responsibility for the electrician. Do not be duped by a low price and a cosy statement that it has been tested, make sure that the way it was tested is relevant to its intended use or regret it at leisure; or possibly at Her Majesty’s pleasure!

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