Fire suppression agents

ESCA has been used to determine the molecular structure of the fluoride lon-induced tnmenzation product of perfluorocyclobutene [74] and the products of the sodium borohydnde reduction of perfluoromdene [75] ESCA is also used to analyze and optimize gas-phase reactions, such as the bromination of trifluoro-methane to produce bromotrifluoromethane, a valuable fire suppression agent [76] The ionization energies for several hundred fluorme-containing compounds are summarized in a recent review [77]... 

The unique combination of properties associated with certain fluonnated methanes and ethanes has led to their widespread use in fire suppression systems The three halogenated fire suppression agents in general use today are bromo-trifluoromethane (CF Br, Halon 1301), bromochlorodifluoromethane (CF2BtCl, Halon 1211) and, in small volumes, primarily in the republics of the former Soviet Union and Eastern European nations, 1,2-dibromotetrafluoroethane (BrCF2Cp2Br, Halon 2402)... 

Deep seated fires may not be fully extinguished by a gaseous fire suppressant agent. 

Halon systems were the ideal fire suppression agent before their implications of environmental impact due to ozone depletion. The industry is gradually phasing out usage of halon systems for this reason. A flowchart to analyze mechanisms to supplement or eliminate Halon systems for electrical or computer processing areas is shown in Figure 11. Some of the prime reasons to eliminate the use of Halon systems is that the facility may be constantly manned with a relatively low fire risk. Other facilities may have a very low combustible load and can be supplemented by highly sensitive fire detection means, such as a VESDA fire detection system. 

For means of protection, the use of water based suppression systems may be a hazard due to the disposal of firewater water, which will freeze quite readily in exposed locations. This may also be the case with exposed hydrocarbon fluid lines that, if isolated, say for an ESD activation, may freeze up due to lack of circulation. This will hamper restart operations for the facility. Typical use in the past has been the reliance on gases fire suppression agents for enclosed area, particularly Halon. Other methods include fire water storage tanks that are kept warm, together with fire mains deeply buried and continually circulated. 

Halon - As employed in the fire protection industry, a gaseous fire suppression agent. Halon is an acronym for halogenated hydrocarbons, commonly bromotrifluoromethane (Halon 1301) and bromochlorodifluoro-methane (Halon 1211). Considered obsolete for fire protection purposes due to a possible environmental impact to the Earth s atmospheric ozone layer and beginning to be phased out or eliminated. 

Refrigerants, Propellants, and Foam Blowing Agents R L Powell Fire Suppression Agents Mark L Robin Organic Fluoropolymers IV IV Schmiegel... 

Fire Suppression Agents Mark L Robin Organic Fluoropolymers IV W Schmiegel... 

This reaction also occurs in products that are made with baking soda, which contains sodium bicarbonate. Sodium bicarbonate makes baked goods rise. It is used as an antacid and in deodorants to absorb moisture and odors. Baking soda can be added to toothpaste to whiten teeth and freshen breath. As a paste, sodium bicarbonate can be used in cleaning and scrubbing. It is also used as a fire-suppression agent in some fire extinguishers. 

NFPA 430, 2.6.1 4.1.2.1 New facility design shall take into account the need for containment to protect the environment from oxidizers, fire suppression agents, and decomposition products. 

The most powerful reagents for extinguishing fires are called halons, because they are organic compounds containing halogen atoms. These compounds are generally either CFCs or BFCs (bro-mofluorocarbons). Here are just two examples of halons that have been extensively used as fire suppression agents ... 

Special consideration for fire protection shall be given to areas in which volatile organic liquids are stored and handled. A fire suppression system using halon gas (or an equivalent substitute) as the fire suppression agent shall be installed. An inert gas purging system may be considered for the liquid tanks. 

The search for a perfect fire suppression agent with zero ODP and GWP value of 1, which is nontoxic and highly efficient against different fires is still on. Recently, perfluoro ethyl isopropyl ketone with zero ODP and GWP of 1 due to its low atmospheric lifetime has been identified as one such molecule. Like HFC-227ea, the perfluoro ethyl isopropyl ketone is also prepared starting from hexafluoropropene. The sequence of reactions [80, 81] involved in its preparation as given below ... 

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