The publishing in February of the new BS 8519:2010 Code of Practice has led to a number of misleading claims being made for some cables, according to Derby-based Draka, with the confusion appearing to have arisen from a misinterpretation of the different test methods required for power and control cables.
The new Standard covers the selection and installation of fire-resistant power and control cable systems for life safety and fire-fighting applications. It replaces BS 7346-6:2005 [Components for smoke and heat control systems. Specifications for cable systems] and calls for power cables to be tested in accordance with BS 8491:2008 [Method for assessment of fire integrity of large diameter power cables for use as components for smoke and heat control systems and certain other active fire safety systems] that itself replaced BS 7346-6: 2005.
The Standard makes clear reference to three categories of circuit that are required to maintain their integrity under defined fire conditions for fire survival times of 30 minutes, 60 minutes and 120 minutes. Appropriate cable tests are identified for each category, giving the relevant British Standard for the assessment of cable performance under fire conditions that might be expected in an actual incident.
However, cables are being promoted as complying with the new Standard and suitable for power applications that have been not ratified in accordance with the relevant Standard, BS 8491. These cables have been tested in accordance with BS EN 50200:2006 [Method of test for resistance to fire of unprotected small cables for use in emergency circuits] and are suitable only as control cables.
Currently, Draka claims, there are just two cables in the UK that meet the power cable requirements of BS 8519:2010. One of these is the company’s FTP120 – until recently called Firetuf Powerplus – a third-party approved SWA [Steel Wire Armoured] power cable that achieves BS 8491’s highest integrated-testing 120-minute rating.
The new Standard has come about because of the increased size, height and complexity of the active fire protection in many high-rise and complex buildings and the adoption of fire engineered solutions. These solutions demand a high level of reliable performance from building services, including the electrical supplies.
BS 8519:2010 also aims to ensure that the level of circuit integrity is not compromised by other elements of the electrical distribution system, including cable glands, terminations, joints and cable support systems. The Standard also makes reference to the recommendations in BS 9999:2008 [Code of practice for fire safety in the design, management and use of buildings] in relation to the design and installation of electrical distribution systems for life safety and fire-fighting equipment.
As a Code of Practice, the aim of BS 8519:2010 is to encourage best practice and takes the form of guidance and recommendations. However, care should be taken to ensure that claims of compliance are not misleading, as any company claiming compliance with a Code is expected to be able to justify any actions that deviate from the Code’s recommendations.
Draka UK is the country’s leading designer and manufacturer of fire performance cables, zero halogen power cables and building wires. The company is part of Netherlands-based Draka Holdings NV, which has over 9,000 employees worldwide. Further details are available by telephone on +44 (0) 1332 345431, by fax on +44 (0) 1332 331237, and via email at sales@draka.com. The company’s website can be found at www.drakauk.com.