6 minute read
Vital support
The 3rd amendment to BS 7671 put the issue of cable management fi rmly under the spotlight, highlighting its potential to save lives, as well as improve the look and ease of installations
By David Adams
The importance of cable management can seem to vary from one job to the next. Sometimes it feels like an afterthought. Sometimes it’s an important last step, ensuring cables and wiring are neatly stowed or hidden, with the best trunking solutions even adding an aesthetically pleasing final touch.
But sometimes it could be a matter of life or death, as has been demonstrated in a number of tragic incidents over the past decade, when firefighters were trapped in burning buildings by cables that had fallen from walls and ceilings because the heat of the fire had destroyed enclosures and fastenings holding them in place.
So the most important recent development in this area is undoubtedly the 3rd amendment to the 17th edition, which was published by the IET in January 2015 and came into force in July of that year. Chapter 52 – Selection and Erection of Wiring Systems – now states that “wiring systems in escape of fire, such as general off ice space, shopfloors, school halls and so on.
There was already a requirement for fire performance cables to be secured using metallic fixings able to withstand the same temperatures and vibrations as the cables themselves within BS 5839 Part 1, but the 3rd amendment now means that this should be extended to all fixings.
> Cable management products are being developed to address fi re safety regulations, speed up installation times and allow cables to be hidden from view
routes shall be supported in such a way that they will not be liable to premature collapse in the event of fire”.
Specific reference is made in Note 1 of the amended regulation to non-metallic trunking being destroyed by fire, leading to cables falling across escape routes; while Note 2 suggests non-metallic clips, cable ties and trunking should not be used as the sole means of support. Escape routes are taken to include not just corridors, stairways and hallways, but also open areas through which people might need to pass in the event
Safety first
There are now many diff erent types of fastening available that could help contractors meet their obligations cost-eff ectively. In places where metallic clips are needed, D-Line’s Safe-D high-temperature steel clips are an option for securing power and/ or security, CCTV or data cables. The
manufacturer points out that because the clips can be used with trunking or attached directly onto walls it is also possible to do without trunking at all in some locations, such as within ceiling voids, thus saving cost and time on installation and rewiring.
Contractors working on large-scale projects are also looking to use cable management hardware such as Legrand’s cable ladders, trays and trunking solutions. Some are seeking certification to back up their choices, although no relevant British or UK standards yet exist, says Nigel Leaver, lead marketing manager for cable management at Legrand. “We’re being asked for trunking systems we can give a fire rating for, but there’s no British or European standard to test to,” he says.
“Traditionally, if people were concerned they’d just go with steel. But people are now looking for certification to back that up, to say how long it will last in the event of a fire. It’s an awkward one, because we don’t have a definitive answer.” He says Legrand’s steel wire mesh trays are tested in accordance with German fire regulation standards, while the industry awaits other standards currently being written.
Darren Staniforth, technical development manager at NICEIC,
Case study: W Portsmouth
Luton-based contractor W Portsmouth has recently started using Legrand’s wire-clipping Swift clip system, most notably on a large warehouse project in Greater Manchester.
“When we started the Greater Manchester project we looked for a bit of cable management that would save time, because there’s so much to do and we have quite tight timescales,” says Luke Royce, contracts manager at W Portsmouth.
The project has entailed installing around 900m of cable trays, mostly at heights of 10m. “The Swift clip system saves the guys so much time and we made savings on buying nuts and bolts and on the time we would have spent handling them,” says Royce. “It’s about fi nding any way we can to reduce labour costs.”
says that, as far as NICEIC is aware, all wiring systems have to comply with the 3rd amendment changes, including data cables and wiring for security systems. He acknowledges that this could cause some practical diff iculties, because other tradesmen may not be aware of the changes. “But it’s something that electricians should be picking up on in their periodic inspections,” he points out.
Easy installation
Aside from the 3rd amendment changes, the other main trend in cable management is work to make installation faster, says Legrand’s Leaver. “You can get to a stage where you can’t get much further on product cost, so you have to look at reducing the time it takes to install the products, which will reduce labour costs,” he explains. “Over the past 10 years we’ve concentrated on making cable management products faster and easier to fit.”
Other cable management products that are proving particularly popular among contractors at present are decorative trunking solutions, according to D-Line business development manager Lee Andrews. “These are proving very popular as a way to hide cables in private homes, or for social housing and housing association re-wires,” he says.
“They are being used for retrofits in hotels – several national and international hotel groups have used our trunking to hide cables leading to wall-mounted TVs and heaters – and for audiovisual equipment installations, or rewiring for fire and security works. It is also popular for historic or listed building refits, where channelling surfaces or lifting floors is impractical.”
For example, earlier this year smart home specialist Avicci used D-Line’s trunking products to hide cabling within a historic property in Scotland, using the products to subtly increase the thickness of skirting boards and doorframes. The client actually had to be shown where the changes had been made as he completely failed to notice them himself on his first walk around the property once the work was complete, says Andrews.
That’s just another example of how good cable management products can help installers complete projects more eff ectively, as well as more cost-eff ectively, while making buildings safer for occupants and firefighters if the worst does happen.
THE POWER TO HELP OVER 3,000 CONTRACTORS DEVELOP EVERY YEAR
BOOK NOW CDM ONLINE COURSE
Get up to speed with the new CDM Regulations!
£40
The right qualifications can make your business more competitive, and we’re giving thousands of contractors an extra edge every year with a wide range of courses.
Our range of courses include: 17th Edition Initial Verification Periodic Inspection PAT Testing Test & Measurement EV Charging Safe Isolation Fire Alarm Design Emergency Lighting Design Plus many more…
All courses now being delivered to Amendment 3 Regulations
To find out where our training could take you, call 0843 290 3401 or email training@certsure.com
