23/11/2024

REGULATIONS FOR FIRE RESISTANT CABLE SUPPORTS - WHAT YOU NEED TO KNOW!

Date: 12/11/2014

This new amendment is nearing its final stages of release and it follows 2013's Second Amendment.  The proposed changes will take effect from 1st January 2015, with new regulations brought into force to tackle the issue of plastic fastenings and fixings.

HellermannTyton’s Richard Rands, Product Manager of Fastenings and Fixings, explains more about the changes ahead and outlines the need for secure and fire resistant products.

What do the new regulations mean?

Under BS7671 of the Electrical Regulations, new requirements outline the need for cabling to be supported by fire-resistant fastenings and fixings which are not liable to premature collapse in extreme heat. This means that plastic cable clips, non-metallic cable ties and plastic trunking to support wiring systems would be unlikely to comply with the new rules. 

The requirements of BS7671 apply to all wiring systems in a building, including those of distribution circuits and final circuits, safety services, and data and communications services. In simple terms, it means that wiring systems should be supported in such a way that they will not collapse when affected by fire, especially around escape routes. The sole use of plastic fixings and non-metallic cable ties will no longer comply with the new regulations and rightly so as exposure to fire could result in the melting of trunking and the risk of loose cabling.

Although bodies such as the NICEIC have recently highlighted the changes through national shows and seminars, many installers may still not be aware that these updates will affect the way they work and the products they use. New measures will have to be taken to ensure compliance which will be vital in ensuring that new installations are safe, with no risk to the installer or anyone else that is entering or present in the building at any particular time.

Why the need for change?

These new rules have been introduced in light of an incident in 2005 which resulted in two firefighters losing their lives when tackling a fire in a block of flats in Stevenage. 

While there were a number of contributing factors to the deaths, one of the firefighters became entangled in electrical cabling that had fallen as a result of the plastic cable trunking in which it was contained melting. The subsequent investigation found that the firefighter had cable insulation stuck on the palm of his glove, indicating that he had been attempting to untangle himself.

The new rules address the greater need for safety when it comes to cable management and support in or near to escape routes. It outlines the requirements that all cables and associated trunking, conduits or cable trays should, wherever possible, be securely attached to suitable fire-resistant parts of the building fabric, using appropriate, non-combustible fixings. This means that cabling near escape routes and exits needs to be supported by fire-resistant fixings.  

How do installers comply with the new rules? 

Previously there had been no clear guidelines on what products should be used in locations where particular risks of fire exist. However, after the tragedy of the 2005 case, it was recognised that standard cable ties and fixings used by installers were not enough to provide safety and security. 

Wiring systems should always be supported in the event of a fire and structural performance should not be affected by increased temperature. The new requirements made by the amendment of BS7671 would be unlikely to be met by the sole use of plastic cables clips, non-metallic cable ties and plastic trunking to support wiring systems which is why stainless steel products are essential in installations.

Stainless steel products are ideal for applications that require high strength, reliability and fire resistance. Although seen by many installers as the more expensive option, hence the use of non-metallic and plastic fixings, stainless steel cable ties can provide essential support and reassurance. Capable of withstanding temperatures of over 500°C, stainless steel cable ties and mounts comply with the new regulations and can significantly reduce the risk of loose wiring and melting trunking. This is why suitable supports should be selected and installed to prevent collapse of the wiring system in the event of a fire.

Installers should therefore look for products that meet high standards of fire resistance, as these will be able to withstand high temperatures and provide durability and strength. For example, products that have London Underground (LU) approval for fire safety will surely provide peace of mind when used in other public places. It is important that installers also look at how the fixing is embedded into the structure and address the need for fire resistant materials not just in the cable tie, but also within the cable mounts and other supportive elements that make up the whole fixing. After all, it’s no use installing a stainless steel cable tie if, in the event of a fire, a plastic element of the fixing such as a wall plug eventually leads to collapse. It is therefore crucial that for long-term security the installation is completely fire resistant as cutting corners could potentially put lives at risk.

When do installers need to consider new measures?

Although the new regulations don’t come into effect until 1st January 2015, installers should start thinking about how they comply with the changes immediately. Carrying out installations with the correct fire resistant cable supports now will mean that fixings are supported and long-term safety is guaranteed. 

Planning now will also ensure tenders and bids being submitted for projects that will commence in 2015 will incorporate the new regulations and provide installers with enough time to research and source new stainless steel products. At present, electrical wholesalers tend to carry limited stock when it comes to such products as metallic cable ties and fixings due to a greater demand for the cheaper plastic alternatives. However, with such changes being introduced, demand for compliant fixings will grow and so it may be effective for installers to change their supply now to avoid a last-minute rush and avoid bulk buying of products that may become redundant come the New Year. 

Where does the use on plastic and non-metallic products stand?

Installers shouldn’t get the idea that the use of plastic ties and other alternatives to stainless steel fixings are completely out of bounds. These products can still be applied to numerous installations that may not need to comply with high fire safety standards. However, installers need to understand that wiring systems should be supported in a way that protects against fire, collapse and loose cabling – especially by or near escape routes.

Installers therefore need to assess each and every project they work on to determine what would be the best course of action and what standards need to be met. Is it really worth cutting corners, opting for the cheaper alternatives or ignoring the regulation standards altogether? The continued use of inefficient and dangerous fixings that will not withstand the intensities of a fire will ultimately lead to the endangerment of lives, so education, understanding and application of high quality and approved products is key to protecting those lives.


*BS7671 - Amendment 2 of the 17th Edition Electrical Regulations, Chapter 52, Section 521.200 – Wiring Systems in Escape Routes.