01 May 2007 12:00pm

Keep on Top of Burning Issues

Fire Engineering, Fire Safety, Non-combustible

Fire resistance has moved back up the construction industry’s agenda, particularly with the Regulatory Reform Fire Safety Order (RRFSO) coming into effect late last year. Richard Wigley, Marketing Manager, from Eurobond, explains the importance of these new regulations and why they will significantly influence end client specifications.

With a revision to Part B of the Building Regulations, which included the introduction of the RRFSO, designers are now being asked to complete a fire risk assessment as the first stage of the design process. This requirement underlines the new fire prevention approach, which asks designers to identify fire risks at an early stage and try to remove them.

With this added responsibility designers will be taking a renewed look at the fire performance of every component they recommend. This actually presents a real opportunity for manufacturers, a new reason to re-introduce products - particularly those with high fire performance credentials.

Accompanying the Fire Safety Order are a number of guides providing further guidance on fire risk assessment and fire precautions. It’s worth manufacturers understanding these guides, and how their products fit in.

For example, insulated core composite panels are highlighted as an area for particular consideration. The guides state that "The potential for fire development involving mineral fibre cores is less than that for composite panels containing polymeric cores. Therefore, in areas where there is a considerable life risk, it may be appropriate to consider replacing combustible composite panels."

For those that have advocated the use of mineral wool core for many years, this is an excellent endorsement, which can be related directly back to a company’s product range – and passed in front of specifiers. In addition, supporting information can be presented, to really build the case.

In terms of the composite wall panel sector, the most important aspect of fire resistance in steel faced panel construction is integrity of panel joints – i.e. the ability to prevent gaps from forming through which flames and hot gases may pass. Since, in a composite panel assembly the fire exposed steel face is expected to expand and bow early in a fire (at around 1000°c) causing opening of the composite panel joints, one of the most important factors, when it comes to limiting fire spread, is the combustibility of the core material.

Eurobond has always championed mineral wool core, as opposed to blown foam, as this non-combustible material won’t ignite in the event of a fire, as the material is made of stone and will not burn. Therefore, with a mineral wool fibre core it doesn't matter if the joints open up, as the core material is unaffected and doesn’t contribute to fire spread.

Eurobond forecasts that this renewed emphasis on fire performance will soon also move onto the associated risks of smoke, and is already pushing this issue with specifiers. Not only can toxic smoke cause significant damage but it poses one of the greatest risks to people in fires.

There are currently only a few application areas where smoke toxicity is included in the regulations. For example, in the IMO regulations for the classification of surface materials for use in the interiors of ships and other transport, there are detailed requirements on smoke toxicity.

However, there is definitely a growing interest and Eurobond welcomed recent independent testing by the Warrington Fire Research Centre, which compared the toxic nature of the fire smoke produced from burning different composite panel core materials.

These results provide specifiers with validated information on the levels of toxic smoke produced by composite panel cores, manufactured from the two most common materials, Polyisocyanurate (PIR) and mineral wool, and present further endorsement for mineral wool cored products.