Fire-extinguishing apparatus

A colourless gas, b.p. — 59-C/740 mm. Used as a relatively non-toxic propellant gas in fire fighting apparatus, e.g. dry-powder extinguishers. Made by the bromination of fluoro-form, CHF3. 

Underwriters Laboratories 333 Pfingsten Road Northbrook, Id. 60062 Standards for Safety is ahst of more than 200 standards that provide specifications and requirements for constmetion and performance under test and in actual use of a broad range of electrical apparatus and equipment, including household appHances, fire-extinguishing and fire protection devices and equipment, and many other nongenerady classifiable items, eg, ladders, sweeping compounds, waste cans, and roof jacks for trader coaches. 

Caution. n-Butyldichloroborane is pyrophoric and must be handled with care (see Properties). All work should be conducted in a vented hood with a fire extinguisher readily available. After completion of the experiment, the apparatus should be cooled to room temperature while being flushed with inert gas. It should then be rinsed immediately with a copious amount of water. 

Electrical fires First disconnect the apparatus or equipment by pulling the safety switch or switch off the mains to avoid possibility of being electrocuted. Then use Class C fire extinguisher. 

Carbon dioxide fire extinguishers are widely used in laboratory fire fighting because the C02 does not damage apparatus or cause electrical shorts. Furthermore, carbon dioxide is effective against a wide variety of fires and is not toxic. The National Fire Protection Association adopts the following classification of fires ... 

Some of the gas dissolves in the aqueous solution, and the gas pressure developed within the apparatus forces the mixture out through the nozzle, which is directed onto the flame. If some heavy molasses or similar gluelike material is added to the sodium carbonate solution and some aluminum sulfate is added to the sulfuric acid, the solution discharges from the nozzle in the form of a foam in which the carbon dioxide gas is trapped. This heavy blanket of foam containing carbon dioxide settles over and around the burning object. The aluminum sulfate hydrolyzes to form aluminum hydroxide, which, at the temperature of the flame, dehydrates to produce a crust of aluminum oxide over the flame. Both effects serve to extinguish the flame. The common Foamite fire extinguisher is an example of this type. 

PERSONAL PROTECTION wear full protective clothing and heat resistant gloves wear chemical safety goggles full-facepiece and self-contained breathing apparatus is recommended at a concentration of lOOmg/m emergency showers and fire extinguishers are recommended around kilns. 

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