Terry Journeaux believes prescriptive cable standards are too limiting and argues that manufacturers and installers should be given more room for choice.
While installers are naturally concerned with a cable’s impact upon the smooth progress and ultimate cost of projects, consultants and engineers place emphasis on compliance with British Standards. The wholesalers are naturally inclined to simply stock what they know they can sell.

Although communications and data transmission cabling have advanced in line with the increasing use of information technology, the same cannot be said for power and lighting cables. Most of the basic products have mainly remained unchanged other than for their fire safety performance. But how many of these improvements have actually benefited the installer?

Much of the blame for any inertia has to point towards the UK’s highly prescriptive standards system. If a manufacturer sticks to the same old thing it has a much better chance of being specified. But this approach does not do the installer any favours as it limits the opportunities to introduce new products with features that will ease installation.

This situation cannot remain unchanged forever because our working practices are going to be influenced by European directives in the near future and these favour a less prescriptive approach. Instead, they concentrate on the essential safety issues, which should lead to more choice for the user.

Contractors should therefore be asking which are the best cables for the most cost-effective installations, and not which specifications should be used simply because all manufacturers’ products are the same. The natural temptation with tight budgets is to substitute one BS compliant cable for another if it costs less. But lowest material cost doesn’t necessarily mean lowest installed cost at the end of the day.

In developing its current generation of fire resistant cables, Pirelli looked to identify the criteria that would satisfy everyone involved in the supply chain. As part of this research, Pirelli carried out qualitative market research with groups of contractors to define the requirements of any new cables that would be developed for the wiring of fire alarm systems. We already knew what the standards and legislation required, what we wanted to find out was what the contractors wanted. And the results were interesting.

At the top of the ‘wish list’ was ease of installation (43%) and this was rated as more important than price (34%) and technical features (17%). Also, 38% of the participants were not satisfied with the flexibility of products on the market at that time. This was largely because of the range of installation methods employed for these jobs, with ‘clipped direct’ being the most common but also with relatively high importance being placed on tray, mini-trunking and within voids. Fitting of cables around moulded corners was identified as a major problem with mini-trunking and available cable designs. In fact, some installers had found it necessary to leave out the corners to get round the problem.

At the end of the research we ended up with a list of installation requirements that would make life easier for the installer. These included ease of termination, ease of handling, resistance to kinking, ease of clipping, ease of trunking installation, resistance to installation damage, size and weight.

On considering this range of requirements, it was clear that no single product could fully satisfy all of these criteria, particularly in relation to the extremes in requirement for ease of clipping and ease of trunking installation. The obvious conclusion was that the products would have to be differentiated for different two new fire resistant cables - FP200Gold, a dressable product for surface-mounted applications and FP200Flex, a pliable product for other installations, such as ceiling voids and trunking.

Earlier this year, the company also launched a new quick-fit FP gland for use with the FP 200 range of fire resistant cables. In a typical installation, hundreds of glands may be required to secure the cabling at alarm panels, call points and other terminations. Once again the gland was designed after consultation with installers and with their needs in mind to save time and reduce costs.

The future lies in differentiated brands that users can rely on to do the job in the most cost-effective way. This can only be achieved by those manufacturers with the R&D capabilities to convert customer demands into reality. There is certainly no future in hiding behind highly prescriptive standards - these are simply a barrier to product innovation and evolution.

Standard Practice

Large shopping complexes sprang up around the country at an alarming rate of knots in the last decade. While out-of-town is now out-of-favour, retail is still big on the High Street. With such huge developments come huge responsibilities for public safety in the event of fire. BS 5588 Part 10 outlines a code of practice for shopping complexes and Section 17 of the standard discusses the controlled evacuation procedures in th event of fire. Within Section 17 it is noted that “live directive public address announcements from control room operators using colour closed-circuit television surveillance of public areas should be used to evacuate areas such as malls, where many people are present and at potential risk.” In order to comply with the regulations, specifiers and contractors must use the correct equipment to supply electrical power to all fire protection and life safety installations within the hazardous areas. This means that considerable attention should be given to not only the routing of cables, but also the positions of terminations, circuit protection facilities and control panels to ensure that there is adequate protection from fire, and that the equipment will operate in the harshest conditions. If cctv is to be used as an emergency evacuation aid it will have to be compliant with BS 5588 Part 10. And, to this end, Draka UK Special Cables has developed Firetuf Coax. The cable is manufactuered from lsoh materials and meets the requirements of BS 6387 Categories C, W and Z. An armoured version is also available on request.

Source

Electrical and Mechanical Contractor

Postscript

Terry Journeaux is technical manager with Pirelli Cables.