Cables Fire resistance

The aryloxyphosphazene polymers, on the other hand, have been used primarily ia wire and cable coatings and jackets and as fire-resistant, low smoke, closed-ceU foams and sound-barrier sheets. 

Specification for 600/1000V and 1900/3300 V armoured electric cables having thermosetting insulation Fire resisting characteristics of electric cables Performance requirements, sample and lest conditions - BS 5467/1997... 

Fire resistance Fans, motors, cabling and controls which are expected to operate under fire conditions must be suitably rated for the temperature expected. 

Polyetheretherketone PEEK is a high-temperature, crystalline engineering TP used for high performance applications such as wire and cable for aerospace applications, military hardware, oil wells and nuclear plants. It holds up well under continuous 450°F (323° C) temperatures with up to 600°F (316° C) limited use. Fire resistance rating is UL 94 V-0 it resists abrasion and long-term mechanical loads. 

Electrical conductors are normally insulated for protection and avoidance of electrical shorting. Typical insulating materials are plastics that can readily bum with toxic vapors. The NEC specifies certain fire resistant rating to electrical cables to lessen the possibility of cable insulation ignitability and fire spread. 

The increasing use of fiber optics for electronic communications poses critical communications risks. The fire resistant requirements of fiber optical cables are currently similar to the requirements of fire resistant ratings applied to electrical cables within the specifications of the NEC. 

Tests for Fire Resistance of Roof Covering Materials, 1983. (similar to ASTM E 108) Tests for Flame Propagation and Smoke Density Values for Electrical and Optical Fiber Cables in Spaces Transporting Environmental Air, 1991. 

Cable trays may be protected by water spray or fire resistant material. Large or fully filled cable trays, particularly those carrying power cables, should also be reviewed for cable overloading that could result in wire overheating and internal fire. 

To protect the control room area from incidents occurring in the support areas, the control room area should be separated from the support areas by minimum 1-hour fire-rated partition walls. All penetrations of the walls, floors, ceilings, and roof for cables, etc. should be closed with an approved sealant having a fire resistance rating of at least one-hour. Approved y4-hour rated (Class B) fire doors equipped with self-closing devices should be installed on all openings between the control room and other portions of the building. 

I n larger MCCs, if the combustible loading gets extensive, then passive fire protection, e.g., fire-resistant cables or passive fire protection should be considered. The practices of using multiple tiers of cable trays or stripping the outer jacket insulation (to make the cable easier to handle after it enters the room or cabinet) are not recommended. 

Hitachi Cable Ltd., Fire-resistant electrically insulating polyolefin compositions, Japanese Patent 04253748, 1992. 

Richter, S. and Schmidt, R., Testing of cables designed for fire resistance, A comparison of U.S. and European standards, Proceedings of 46th International Wire and Cable Symposium, Philadelphia, PA, 1997, pp. 752-760. 

UL 2196 Standard for Tests for Fire Resistive Cables, UL, Northbrook, IL, 2006. 

Velsicol Chemical LLC, formerly Velsicol Chemical Corporation, designs, manufactures, markets and distributes high performance specialty chemicals and industrial intermediates, primarily based on benzoic acid and the organic compound cyclopentadiene. Its products include chlorendic anhydride and hexachlorocyclopentadiene (HEX). Chlorendic anhydride is corrosion resistant, fire resistant and has high UV stability, and is used in the synthesis of flame retardant polymers such as polyurethanes, unsaturated polyester and epoxy resins. HEX, a reactive intermediate used in the manufacture of agricultural pesticides in the production of flame retardants for the wire and cable industry and in the preparation of chlorendic anhydride. The company s products are produced primarily at a plant in Memphis, Tennessee Velsicol also maintains the Memphis Environmental Center (MEC), which focuses on managing legacy environmental liabilities. The firm is owned by Arsenal Capital Partners, a private equity firm. 

This copolymer can be obtained from a polydimethylsiloxane that has aminoalkyl end groups in a reaction with the polyetherimide formed from the reaction of a bis(ether anhydride) with diaminobenzene. The material is fire resistant and is used in cable insulations. Among other more complex copolymers with practical applications are poly[2,2-propanebis(4-phenyl)-carbonate]-b/ock-poly(dimethylsiloxane)] and a silicone phenol formaldehyde copolymer obtained in two steps, the first being the heating of a polydimethylsiloxane that has reactive end groups with glycerol, and the second step being the reaction with a phenol formaldehyde resin. 

Application of fire retardant and fire resistant cables Reference... 

Application of Fire Retardant and Fire Resistant Cables... 

The application of fire retardant and fire resistant cables to particular services can be shown in tabular form, see Table 9.37 below. 

Table 9.37. Application of fire retardant and fire resistance cables in a typical oil industry plant...

BS7629 Part 1 Specification for 300/500 V fire resistance electric cables having low emission of smoke and corrosive gases when affected by fire. Multicore cables (renamed in 1997). Part 2 Specification for 300/500 V fire resistant electric cables having low emission of smoke and corrosive gases when affected by fire. Multipair cables (renamed in 1997). 

BS7846 Electric cables. 600/1000 V armoured fire-resistant cables having thermosetting insulation and low emission of smoke and corrosive gases when affected by fire. 

BS7917 Elastomer insulated fire resistant (limited circuit integrity) cables for fixed wiring in ships and on mobile and fixed off-shore units. Requirements and test methods. 

Low Density Polyethylene A branched-chain thermoplastic with density 0.91-0.94 g/cm. Has good impact strength, flexibility, transparency, chemical resistance, dielectric properties, and low water permeability and brittleness temperature, but poor heat, stress cracking, fire resistance, and weatherability properties. Processed by extrusion coating, injection and blow-molding, and film extrusion. Can be cross-linked. Used in packaging and shrink films, toys, bottle caps, cable insulation, and coatings. Also called LDPE. 

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