Smoke resistance

Exhaust gases Smoke Resistive sensors pellistors, oxygen-sensors, metal-oxide sensors Hybrid or integrated Hybrid or integrated... 

Whenever the effects of smoke will affect personnel adequate respiratory protection must be provided, such as smoke resistant barriers and fresh air supplies. 

Drysdale, DD. 1995. Fundamental fire properties of combustable materials. In Improved Fire and Smoke Resistant Materials for Commercial Aircraft Interiors A Proceedings, Washington, DC National Academy Press, pp. 31-44. 

National Research Council, National Materials Advisory Board (1995) Fire- and Smoke-Resistant Interior Materials for Commercial Transport Aircraft. Publication Number NMAB-477-1. Washington, DC National Academy Press. 

Fire retardant resin systems can perform quite well in terms of fire and smoke resistance, although low flammability does not necessarily imply low smoke. Unfortunately there can be adverse effects on processing, mechanical properties or chemical resistance. 

Phenolic resins are cured by a condensation reaction using hot press molding and are relatively cheap, having good high temperature performance (230°C), excellent fire and smoke resistance and good resistance to acids. 

Alpha Owens-Coming offers a flame retardant vinyl ester resin that meets ASTM 84 Class 1 flame spread and smoke rating. The resin is a highly brominated bisphenol-A epoxy based vinyl ester. It provides a unique combination of good flame and smoke resistance and inherently good mechanical properties. The flexural strength of 34% glass composite is 5100 psi (35 MPa) and flexural modulus is 450 ksi (3.1 GPa). 

Tewarson, A. Improved Fire and Smoke Resistant Materials in Ref [2]. 

Firefighters from the Granite Mountain Hotshots of the nearby Prescott Fire Department were fighting the fire. The erratic fire movement apparently trapped the team. They deployed fire shelters and heat- and smoke-resistant enclosures. Nineteen firefighters lost their lives. This was the greatest loss of firefighters in a wildfire in many years. 

S. A. Hasselbrack, in Improved Fire- and Smoke-Resistant Materials for Commercial Aircraft Interiors, National Materials Advisory Board, National Academies Press, Washington, 1995, pp. 165-174. 

Whenever the dangerous effects of smoke will affect personnel, adequate respiratory protection must be provided, such as adequate measures to evacuate from its effects, smoke resistant barriers/shelter-in-place program, alternative fixed fresh air supplies, or portable self-contained breathing equipment (see Table 5.2). 

Fillers not only reduce the costs of composites, but also frequently impart performance improvements which might not otherwise be achieved by the reinforcement and resin ingredients alone. Fillers can improve fire and smoke resistance by reducing organic content in composite laminates. Other important properties that can be improved through the proper use of fillers include water resistance, weathering, surface smoothness, stiffness, dimensional stability, and temperature resistance. Calcium carbonate is the most widely used inorganic filler. It is available at low cost in a variety of particle sizes and surface treatments. 

LSFR additive, a proprietary flame retardant synergist, meets the increasing demand for PVC and other polymer products that are not only fire resistant, but smoke resistant as well. Further, LSFR enhances the physical properties of polymers in six additional ways, making it one of the most cost-effective flame retardant additives available. In addition, it offers low specific gravity euid bulk density, and no compromise to your compound s physical integrity. 

The industrial value of furfuryl alcohol is a consequence of its low viscosity, high reactivity, and the outstanding chemical, mechanical, and thermal properties of its polymers, corrosion resistance, nonburning, low smoke emission, and exceUent char formation. The reactivity profile of furfuryl alcohol and resins is such that final curing can take place at ambient temperature with strong acids or at elevated temperature with latent acids. Major markets for furfuryl alcohol resins include the production of cores and molds for casting metals, corrosion-resistant fiber-reinforced plastics (FRPs), binders for refractories and corrosion-resistant cements and mortars. 

Corrosion Resistant Fiber-Reinforced Plastic (FRP). Fiber glass reinforcement bonded with furfuryl alcohol thermosetting resias provides plastics with unique properties. Excellent resistance to corrosion and heat distortion coupled with low flame spread and low smoke emission are characteristics that make them valuable as laminating resins with fiber glass (75,76). Another valuable property of furan FRP is its strength at elevated temperature. Hand-layup, spray-up, and filament-win ding techniques are employed to produce an array of corrosion-resistant equipment, pipes, tanks, vats, ducts, scmbbers, stacks, and reaction vessels for industrial appHcations throughout the world. 

The inherent fire resistance and low smoke properties of furan resins appear to be related to the high degree of charring that takes place with minimum evolution of volatiles when exposed to fire. 

Molybdenum Oxides. Molybdenum was one of the first elements used to retard the flames of ceUulosics (2). Mote recently it has been used to impart flame resistance and smoke suppression to plastics (26). Molybdic oxide, ammonium octamolybdate, and zinc molybdate ate the most widely used molybdenum flame retardants. Properties ate given in Table 5. These materials ate recommended almost exclusively for poly(vinyl chloride), its alloys, and unsaturated polyesters (qv). 

Molybdenum Oxide. Molybdenum compounds incorporated into flexible PVC not only increase flame resistance, but also decrease smoke evolution. In Table 10 the effect of molybdenum oxide on the oxygen index of a flexible PVC containing 50 parts of a plasticizer is compared with antimony oxide. Antimony oxide is the superior synergist for flame retardancy but has Httle or no effect on smoke evolution. However, combinations of molybdenum oxide and antimony oxide may be used to reduce the total inorganic flame-retardant additive package, and obtain improved flame resistance and reduced smoke. 

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. 

The newer open-ceU foams, based on polyimides (qv), polyben2imida2oles, polypyrones, polyureas, polyphenylquinoxalines, and phenoHc resins (qv), produce less smoke, are more fire resistant and can be used at higher temperatures. These materials are more expensive and used only for special appHcations including aircraft and marine vessels. Rigid poly(vinyl chloride) (PVC) foams are available in small quantities mainly for use in composite panels and piping appHcations (see Elame retardants Heat-RESISTANTPOLYA rs). 

Elame-spread and smoke-density values, and the less often reported fuel-contributed semiquantitive results of the ASTM E84 test and the limited oxygen index (LOI) laboratory test, are more often used to compare fire performance of ceUular plastics. AH building codes requite that ceUular plastics be protected by inner or outer sheathings or be housed in systems aH with a specified minimum total fire resistance. Absolute incombustibHity cannot be attained in practice and often is not requited. The system approach to protecting the more combustible materials affords adequate safety in the buildings by aHowing the occupant sufficient time to evacuate before combustion of the protected ceUular plastic. 

Proprietary blend formulations based on polysulfone, polyethersulfone, and polyphenylsulfone are sold commercially by Amoco Corporation to meet various end use requirements. The blends based on polysulfone are sold under the MINDEL trademark. A glass fiber-reinforced blend based on PES is offered under the trade name RADEL AG-360. This offers most of the performance characteristics of 30% glass fiber-reinforced polyethersulfone but at a lower cost. Two blend product lines are offered based on PPSF. These are designated as the RADEL R-4000 and R-7000 series of products. The former is a lower cost alternative to RADEL R PPSF homopolymer offering most of the performance attributes unique to PPSF. The R-7000 series of resins have been formulated for use in aircraft interiors for civil air transport. They exhibit a very high degree of resistance to flammabihty and smoke release. 

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