Flame Retardant and Fire Resistant Cables

UNDERSTANDING THE DIFFERENCE OF FLAME RETARDANT and FIRE RESISTANT CABLES

Whenever public space is planned, ‘planning for the worst’ keeps step.  Fire and disaster planning is painstaking, so it is of the utmost importance that specifiers and contractors understand when to use Flame Retardant and when to use Fire-resistant cable, what the differences are and how the right choices should be arrived at.  

Flame retardant cables are designed to resist the spread of fire into a new area. Fire resistant cables are designed to maintain circuit integrity and continue to work for a specified period of time under defined conditions.

Both have an important part to play in preserving the integrity of the environment during a fire incident and improving the chances of escape and survival.

Flame Resistance

Tratos’ flame resistant cable meets flame propagation testing BS EN 60332, EN 50265 and BS 4066

Typical applications for Tratos’ fire resistant cable include public buildings from schools to hospitals, underground and overground railway stations, retail and leisure venues as well as offshore vessels and hazardous environments such as Oil & Gas platforms. The manufacturer can supply a complete range of fire resistant cables to comply with the latest Standards and Codes of Practice covering fire detection, alarm systems, emergency lighting or other vital power supplies. Tratos has comprehensive modern fire testing facilities on-site to ensure cable integrity. Thanks to this facility Tratos can produce cables for international projects that meet multiple nations’ standards. Tratos Firesafe cables are manufactured in accordance with all the relevant standards: find out more in the products section:

Flame Retardant

Tratos’ flame retardance cables encompass a range of low smoke and fume cables, designed and tested to resist flame propagation and spread and offering low toxicity, smoke and acid gas generation.

Tratos Firesafe cables are manufactured in accordance with the following British Standards:

• BS 7211 Electric cables. Thermosetting insulated and thermoplastic sheathed cables for voltages up to and including 450/750 V for electric power and lighting and having low emission of smoke and corrosive gases when affected by fire.
• BS 7629 Electric cables. Specification for 300/500 V fire resistant screened cables having low emission of smoke and corrosive gases when affected by fire Multicore and multipair cables.
• BS 7846 Electric cables. Thermosetting insulated, armoured, fire-resistant cables of rated voltage 600/1000 V, having low emission of smoke and corrosive gases when affected by fire.

When correctly selected and installed fire resistant cables supplied by Tratos meet the following Codes of Practice:

• BS 5266-1 Emergency lighting Code of practice for the emergency escape lighting of premises.
• BS 5839-1 Fire detection and fire alarm systems for buildings Code of practice for design, installation, commissioning and maintenance of systems in non-domestic premises.
• BS 7346-7 Components for smoke and heat control systems Code of practice on functional recommendations and calculation methods for smoke and heat control systems for covered car parks.
• BS 8519:2010 Code of practice Selection and installation of fire-resistant power and control cable systems for life safety and fire-fighting applications.
• BS 9999:2008 Fire safety code of practice for the design, management and use of buildings.

Whatever your requirements,  as the actual manufacturer rather than a distributor, Tratos can supply you with both copper and fibre optic cables of guaranteed performance and quality having:

• Fire integrity
• Resistance to combustion
• Flame retardance
• Low flame propagation and flames spread
• Low toxicity and smoke
• Low acid gas generation
• Combined with Pliability to easy installation

Tratos supplies “standard” and “enhanced” grade fire resistant cables to suit the actual installation, large or small, simple or complex in accordance with the applicable Code of Practice. Alongside Firesafe cables, Tratos offers a selection of accessories including glands, p-clips and saddles in Low Smoke Zero Halogen (LSOH) from stock to suit all Tratos Firesafe cables.

There are important differences between LSF (Low Smoke and Fume) and LSHF (Low Smoke Halogen Free) cables.  LSF is a term used originally by the MOD(N) to describe cables with a high oxygen index, high-temperature index CSP sheathing compound. These cables were claimed to have improved performance in fire, and the MOD(N) termed these Low smoke and fume cables. The smoke emission of the CSP sheathing compound was evaluated using the NBS smoke chamber.  

Although an improvement over cables sheathed with traditional CSP, unfortunate events in the Falklands war lead to the development of much improved compounds. In the commercial cable market, the term LSF began to be used to cover any cable with a high oxygen index or temperature index coupled with reduced emission of smoke, including halogenated materials such as PVC, CSP and PCP.  LSHF is not a true technical term, it is one some companies use to describe their Low Smoke Halogen Free cables, while others use their own descriptors such as Low Smoke O (zero) Halogen (LSOH), Low Smoke Zero Halogen (LSZH), Low Smoke No Halogens (LSNH).  Fire safety advances in cable production have had a particular focus on PVC.

PVC & FIRE

Burning PVC gives off poisonous gasses, in particular hydrogen chloride (HCL). When HCL combines with moisture it forms hydrochloric acid; life-threatening and corrosive to electronics, metal surfaces and buildings. Zero halogen cables, with their inhibited production of dense black smoke, significantly increase the chances of escape.  Low smoke halogen-free cables also lower the risk of fumes causing choking and reduce the likelihood of acidic gas damaging electronic equipment. While LSHF cables emit no more than 0.5% hydrogen chloride during fire tests, some LSF cables are made from a modified version of PVC and can still give off significant levels of dense smoke and hydrogen chloride gas when burned.  They still have a place, but they have no place in public spaces or where equipment will be exposed to damage.

Tratos Testing Facility

As an innovation-driven company working to develop bespoke cable alongside researching the best of next-generation product performance, Tratos felt it was critical to invest in its own on-site test facility – with fire-testing at the top of the agenda. Its UK & Italy fire-testing facilities are second to none, giving Tratos’ customers cable that is tested against, passes and often exceeds, minimum standards.  The company manufactures the highest quality cable and, because it serves customers worldwide, it has to ensure its products are compliant with international standards.  The test facility handles standard tests for voltage, spark test and resistance, as well as more in-depth tests for elongation, heat shock, shrink back and vertical flame tests.

These tests and measurements are wide-ranging, exploring available safe egress (ASET), area burning rate, backdraft, burning behaviour, char, combustion, deflagration, ease of ignition, fire load density, fire resistance, flame spread, linear and mass burning rates, the opacity of smoke, oxygen index performance and more. Tratos’ test facilities include a CPR (BS EN 50399) Test Rig, small scale (Bunsen burner test) BS EN 60332-1, large scale vertical propagation BS EN IEC 60332-3, Smoke density – 3 m3 BS EN 61034  and NBS Smoke Density Chamber, Acid gas emission BS EN 60754, test on gases evolved during combustion of materials from cables. Determination of halogen acid gas content, Limiting Oxygen Index (LOI) – ASTM D2863 and Flammability Temperature Index (FTI) – ISO 4589-3.  For the detail behind the Standards.

Firesafe cables made by Tratos have been tested and certified by LCPB, UKAS, BSI, LUR & IMQ.

Cable manufactured based on:

• BS 7211, BS 7629, BS 7846
• Fire Performance based on:
• International – IEC 60331
• European Standards – BS EN 50200, BS EN 50267, BS EN 60332, BS EN 61034
• UK Standards – BS 8434, BS 8491
• Applicable Codes of Practice:
• UK Standards – BS 5266, BS 5839, BS 7346, BS 8519, BS 9999

Note: This is an indicative range of Standards to which Tratos manufacture cables. Cables manufactured in accordance with other Standards are available on request.

TRATOS FIRESAFE-OPTI®

FIresafe Fibre Optic cables have an important role to play. LOW SMOKE ZERO HALOGEN (LSZH) CABLES offer enhanced circuit integrity when exposed to fire. Tratos Firesafe OPTI has been designed for areas where optical fibre cables are required to operate in the event of a fire, for example, railway and highways tunnels, mass transit underground systems, metro lines, ducts and public buildings.

STANDARDS

• CEI IEC 60331-11 Ed. 1999 equivalent CEI 20-36/1-1 Ed. 1 2003-03: Test for electric cables under re conditions Part 11 apparatus fire alone at flame temperatures of at least 750°C
• CEI OEC 60331-25 Ed. 1999 equivalent CEI 20-36/2-5 Ed. 1 2002-03: Test for electrical cables under fire conditions – circuits integrity part 25 procedures and requirements optical bre cables

Other Fire Resistant Cables in the family include:

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TRATOS FIRESAFE-SWA/M1®
600/1000 V ARMOURED – LOW SMOKE ZERO HALOGEN (LSZH) CABLES HAVING ENHANCED CIRCUIT INTEGRITY WHEN EXPOSED TO FIRE – BASED ON BS7846

Tratos Firesafe SWA/M1 is designed for installations where a fire situation may pose a hazard and the maintenance of circuit integrity is a requirement. Applications include internal and external use in public buildings, schools, hospitals, department stores, cinemas, hotels, theatres, computer centres and similar applications where an armoured “enhanced” grade cable is specified for use in the applicable Code of Practice: BS 5266 Emergency lighting cables – enhanced, BS 5839 Clause 26.2e Enhanced grade, BS 8519 Category 1, 2  and 3 (when tested in Tratos laboratories; pending third party approval).

STANDARDS

• BS 7846 F2; Manufacturing and test standard
• BS 6387; Categories C, W & Z
• BS 8434-2 enhanced
• BS EN 50200; PH30, PH60, PH120
• BS 8491; PH30, PH60, PH120*
• BS EN 60332-1 and BS EN 60332-3; Flame propagation
• BS EN 50267; Acid gas emission
• BS EN 61034; Smoke emission

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TRATOS FIRESAFE-TW950E®
300/500 V – LOW SMOKE ZERO HALOGEN (LSZH) CABLES

HAVING ENHANCED CIRCUIT INTEGRITY WHEN EXPOSED TO FIRE – BASED ON BS7629

Tratos  Firesafe TW950e is designed for installations where a fire situation may pose a hazard and the maintenance of circuit integrity is a requirement. Applications include public buildings, schools, hospitals, department stores, cinemas, hotels, theatres, computer centres and similar applications where “enhanced” grade cable is specified for use in the applicable Code of Practice: BS 5266 Emergency lighting cables – enhanced, BS 5839 Clause 26.2e Enhanced grade, BS 8519 Category 1, 2  and 3 (when tested in Tratos laboratories; pending third party approval).

STANDARDS

• BS 7629; Manufacturing standard
• BS 6387; Categories C, W & Z
• BS 8434-2 enhanced
• BS EN 50200; PH30, PH60, PH120
• BS EN 60332-1 and BS EN 60332-3; Flame propagation
• BS EN 50267; Acid gas emission
• BS EN 61034; Smoke emissionT

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TRATOS FIRESAFE-TW950S®

300/500 V – LOW SMOKE ZERO HALOGEN (LSZH) CABLES HAVING STANDARD CIRCUIT INTEGRITY WHEN EXPOSED TO FIRE – BASED ON BS7629

Tratos Firesafe TW950s is designed for installations where a fire situation may pose a hazard and the maintenance of circuit integrity is a requirement. Applications include public buildings, schools, hospitals, department stores, cinemas, hotels, theatres, computer centres and similar applications where “standard” grade cable is specified for use in the applicable Code of Practice: BS 5266 Emergency lighting cables – standard, BS 5839 Clause 26.2d Standard grade, BS 8519 Category 1 and 2 (When tested in Tratos laboratories; pending third party approval).

STANDARDS

• BS 7629; Manufacturing standard
• BS 6387; Categories C, W & Z
• BS EN 50200; PH30 (30 minutes annex E)
• BS EN 60332-1 and BS EN 60332-3; Flame propagation
• BS EN 50267; Acid gas emission
• BS EN 61034; Smoke emission

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TRATOS FIRESAFE-TW100®
450/750V – LOW SMOKE ZERO HALOGEN (LSZH) CABLES HAVING ENHANCED CIRCUIT INTEGRITY WHEN EXPOSED TO FIRE – BASED ON BS7211

Tratos Firesafe TW100 is designed for installations where a fire situation may pose a hazard and the maintenance of circuit integrity is a requirement. Tratos Firesafe TW100 is suitable for installations in onerous conditions where the cable is mechanically protected in metal conduit or trunking. Applications include public buildings, schools, hospitals, department stores, cinemas, hotels, theatres, computer centres and similar applications where “standard” grade cable is specified for use in the applicable Code of Practice: BS 5266 Emergency lighting cables, standard and enhanced when enclosed in screwed steel conduit.

STANDARDS

• BS 7211 Manufacturing standard with an additional mica-glass fire resistant tape.
• BS 6387; Categories C, W & Z (when applied to a single cable)
• IEC 60331; with the flame temperature increased to 950 oC
• BS EN 50200: when installed in screwed steel conduit
• BS EN 50200 Annex E: when installed in screwed steel conduit
• BS EN 60332-1 and BS EN 60332-3; Flame propagation
• BS EN 50267; Acid gas emission
• BS EN 61034; Smoke emission

Click on the link for more information on TRATOS FIRESAFE-TW100®.

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Tratos Firesafe range meets CPR regulation:

*CPR

Tratos was an early supporter of The Construction Products Regulation or CPR.  CPR assesses construction products’ performance throughout the EU. With CPR, Industry professionals, public authorities and consumers can compare the performance of products from different manufacturers in different countries.  Find out more, here https://tratosgroup.com/quality/cpr/