The mile Hudson River is steeped in American history.
Classes[ edit ] Both Reactive and Additive Flame retardants types, can be further separated into several different classes: Minerals such as aluminium hydroxide ATHmagnesium hydroxide MDHhuntite and hydromagnesite     various hydratesred phosphorusand boron compounds, mostly borates.
This class includes organochlorines such as chlorendic acid derivatives and chlorinated paraffins ; organobromines such as decabromodiphenyl ether decaBDEdecabromodiphenyl ethane a replacement for decaBDEpolymeric brominated compounds such as brominated polystyrenes, brominated carbonate oligomers BCOsbrominated epoxy oligomers BEOstetrabromophthalic anyhydride, tetrabromobisphenol A TBBPA and hexabromocyclododecane HBCD.
Most but not all halogenated flame retardants are used in conjunction with a synergist to enhance their efficiency. Antimony trioxide is widely used but other forms of antimony such as the pentoxide and sodium antimonate are also used.
Such compounds include tris 2,3-dibromopropyl phosphate brominated tris and chlorinated organophosphates such as tris 1,3-dichloropropyl phosphate chlorinated tris or TDCPP and tetrakis 2-chlorethyl dichloroisopentyldiphosphate V6.
Most of the organohalogen and organophosphate compounds also do not react permanently to attach themselves into their surroundings but further work is now underway to graft further chemical groups onto these materials to enable them to become integrated without losing their retardant efficiency.
This also will make these materials non emissive into the environment.
Certain new non halogenated products, with these reactive and non emissive characteristics have been coming onto the market sincebecause of the public debate about flame retardant emissions.
Retardation mechanisms[ edit ] The basic mechanisms of flame retardancy vary depending on the specific flame retardant and the substrate. Additive and reactive flame-retardant chemicals can both function in the vapor gaseous or condensed solid phase. Endothermic degradation[ edit ] Some compounds break down endothermically when subjected to high temperatures.
Magnesium and aluminium hydroxides are an example, together with various carbonates and hydrates such as mixtures of huntite and hydromagnesite. The use of hydroxides and hydrates is limited by their relatively low decomposition temperature, which limits the maximum processing temperature of the polymers typically used in polyolefins for wire and cable applications.
Thermal shielding solid phase [ edit ] A way to stop spreading of the flame over the material is to create a thermal insulation barrier between the burning and unburned parts.
Intumescent additives are often employed; their role is to turn the polymer surface into a char, which separates the flame from the material and slows the heat transfer to the unburned fuel. Non-halogenated inorganic and organic phosphate flame retardants typically act through this mechanism by generating a polymeric layer of charred phosphoric acid.
Use and effectiveness[ edit ] Fire safety standards[ edit ] Flame retardants are typically added to industrial and consumer products to meet flammability standards for furniture, textiles, electronics, and building products like insulation.
Although no other U. The proliferation of flame retardants, and especially halogenated organic flame retardants, in furniture across the United States is strongly linked to TB In response to concerns about the health impacts of flame retardants in upholstered furniture, in February California proposed modifying TB to require that fabric covering upholstered furniture meet a smolder test and to eliminate the foam flammability standards.
Jerry Brown signed the modified TB in November and it became effective in However, these questions of eliminating emissions into the environment from flame retardants can be solved by using a new classification of highly efficient flame retardants, which do not contain halogen compounds, and which can also be keyed permanently into the chemical structure of the foams used in the furniture and bedding industries.
The resulting foams have been certified to produce no flame retardant emissions. This new technology is based on entirely newly developed "Green Chemistry" with the final foam containing about one third by weight of natural oils.
Use of this technology in the production of California TB foams, would allow continued protection for the consumer against open flame ignition whilst providing the newly recognized and newly needed protection, against chemical emissions into home and office environments.
One of the most demanding flammability tests worldwide is probably the US Federal Aviation Authority test for aircraft seating which involves the use of a kerosene burner which blasts flame at the test piece.
The Greenstreet Berman study, carried out by the UK government, showed that in the period between and the UK Furniture and Furnishings Fire Safety Regulations accounted for 54 fewer deaths per year, fewer non-fatal casualties per year and fewer fires each year following the introduction of the UK furniture safety regulations in In particular, they looked at maximum heat release and time to maximum heat release, two key indicators of fire danger.
These studies found that the type of fabric covering had a large influence on ease of ignition, that cotton fillings were much less flammable than polyurethane foam fillings, and that an interliner material substantially reduced the ease of ignition.
Mainly brominated flame retardants were found in many environmental compartments and organisms including humans, and some individual substances were found to have toxic properties. Therefore, alternatives have been demanded by authorities, NGOs and equipment manufacturers.
In order to make the evaluation fully comprehensive, it was decided to compare also material and fire performance as well as attempt a life cycle assessment of a reference product containing halogen free versus brominated flame retardants.
About a dozen halogen free flame retardants were studied representing a large variety of applications, from engineering plastics, printed circuit boardsencapsulants to textile and intumescent coatings.
A large group of the studied flame retardants were found to have a good environmental and health profile: Overall, they were found to have a much lower tendency to bioaccumulate in fatty tissue than the studied brominated flame retardants.
The tests on the fire behaviour of materials with different flame retardants revealed that halogen free flame retardants produce less smoke and toxic fire emissions, with the exception of the aryl phosphates RDP and BDP in styrenic polymers.
The leaching experiments showed that the nature of the polymer is a dominating factor and that the leaching behaviour of halogen free and brominated flame retardants is comparable.
However, moulded plates which represent real world plastic products showed much lower leaching levels than extruded polymer granules. The impact assessment studies reconfirmed that the improper waste and recycling treatment of electronic products with brominated flame retardants can produce dioxins which is not the case with halogen free alternatives.
Inthe U. Health concerns[ edit ] The earliest flame retardants, polychlorinated biphenyls PCBswere banned in the U. While the demand for brominated and chlorinated flame retardants in North America and Western Europe is declining, it is rising in all other regions.The Hudson River and PCB Pollution The Hudson River is a body of water that stretches for miles from the Adirondack Mountains to the Battery in Manhattan, reaching its deepest point of feet in the Highlands near Constitution Island and West Point and reaches its widest point of 3 miles across at Havestraw.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research. Aug. 22 — More work is needed to remove polychlorinated biphenyls from the upper Hudson River despite the completion of a six-year dredging project by General Electric Co., the state Department of Environmental Conservation (DEC) .
Hudson River PCBs Superfund Site. EPA Expands Scope of Hudson River Cleanup Analysis. Agency Begins Analysis of State Sediment Samples and Advances Work in Floodplain ; General Electric - Hudson Dredging. Other PCB Sediment Sites. Multimedia. Video: Returning a River to Health.
News Feeds;. The term flame retardants subsumes a diverse group of chemicals which are added to manufactured materials, such as plastics and textiles, and surface finishes and coatings. Flame retardants are activated by the presence of an ignition source and are intended to prevent or slow the further development of ignition by a variety of different physical and chemical methods.
Climate Science Glossary Term Lookup. Enter a term in the search box to find its definition. Settings. Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).