Heat release rate is the key property in fires. This survey investigates the effect of flame retardants on the heat released by key polymers. The polymeric materials were chosen based on two criteria: that they be used extensively in key applications (building/construction, furniture/furnishings, transportation or electrical/electronics) and that their intrinsic fire performance not be good enough for adequate fire safety. The following materials were chosen (in alphabetical order). 1. ABS and/or other styrenics, including HIPS 2. Cellulose or cotton fabrics 3. Engineering thermoplastics (including polycarbonate) 4. Epoxy resins 5. EVA and/or other polyolefin blends and/or copolymers 6. Flexible PVC 7. LDPE 8. Nylon and/or other polyamides 9. Polyesters (including also PET fabrics) 10. Polycarbonate 11. Polypropylene 12. Polystyrene 13. Polyurethane (foam and thermoplastic polyurethane) 14. Rigid PVC 15. Wood (different species, if possible) A pair of publications in the 2014 Fire and Materials journal has gone into extensive detail on this subject and the present publication was designed to summarize the findings. Most of the studies reviewed here (well over 100) were conducted primarily in the initial 21st century years, and are, undoubtedly, of uneven quality. Moreover, many of the studies are also academic and not based on actual commercial products. Therefore the survey of new date should be used in combination with earlier studies, including particularly a seminal 1988 NBS/NIST study that focused on 5 materials made into simulated products. Some important observations can be developed: (1) the fact that a material has been “flame retarded” simply means that some amount of “flame retardants” has been added: such a system does not necessarily have proper fire performance, (2) the designation of a material as “flame retardant” (or even, more accurately, as “flame retarded”) is a meaningless and misleading designation as it is not related to actual fire performance, (3) improvements in fire performance are typically intended to meet certain fire safety requirements and (3) flame retardants (individually or in combination) that can be efficient for a particular polymer can be useless for other materials. In some systems improvements in heat release rate of over an order of magnitude can be found. The key conclusion to be drawn from the work is that flame retardants will decrease heat release rates of polymers. However, it is essential that flame retardant systems be used for the correct application and in the proper proportions. Thus, the proper use of flame retardants will lead to lower fire hazard.
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