Search results
Results from the WOW.Com Content Network
Exposure to Halon 1301 in the 5% to 7% range produces little, if any, noticeable effect. At levels between 7% and 10%, mild central nervous system effects such as dizziness and tingling in the extremities have been reported. [8] In practice, the operators of many Halon 1301 total flooding systems evacuate the space on impending agent discharge.
[citation needed]) Halon 1211 also has low toxicity, although it is more toxic than Halon 1301, and thus considered unsuitable for flooding systems. However, Halon 1301 fire suppression is not completely non-toxic; very high temperature flame, or contact with red-hot metal, can cause decomposition of Halon 1301 to toxic byproducts.
Halon 1301 and 1211 are being replaced with new halocarbon agents which have no ozone depletion properties and low atmospheric lifetimes, but are less effective. Halon 2402 is a liquid agent (dibromotetrafluoroethane) which has had limited use in the West due to its higher toxicity than 1211 or 1301.
In the early 20th century, carbon tetrachloride was extensively used as a dry cleaning solvent, a refrigerant and as a fire extinguishing agent. In time, it was found carbon tetrachloride could lead to severe health effects. [7] From the mid-1960s Halon 1301 was the industry standard for protecting high-value assets from the threat of fire ...
e. Agent Orange is a chemical herbicide and defoliant, one of the tactical use Rainbow Herbicides. It was used by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, [1] during the Vietnam War from 1961 to 1971. [2] The U.S. was strongly influenced by the British who used Agent Orange during the Malayan Emergency.
Montreal Protocol enforced a phased ban on halon-based products. Pyrotechnically generated aerosol extinguishing agent (PGAEA) was first suggested by Senecal in 1992. [7] The United States Environmental Protection Agency has approved condensed aerosol fire suppression systems as acceptable substitutes for Halon 1301 in total flooding systems. [8]
The HFC-227ea fire suppression agent was the first non-ozone-depleting replacement for Halon 1301. [citation needed] In addition, HFC-227ea leaves no residue on valuable equipment after discharge. [2] HFC-227ea contains no chlorine or bromine atoms, presenting no ozone depletion effect. Its atmospheric lifetime is approximated between 31 and 42 ...
Bromochloromethane or methylene bromochloride and Halon 1011 is a mixed halomethane. It is a heavy low-viscosity liquid with refractive index 1.4808. Halon 1011 was invented for use in fire extinguishers in Germany during the mid-1940s, in an attempt to create a less toxic, more effective alternative to carbon tetrachloride .