1522
JOURNAL OF CHEMICAL EDUCATION
SEPTEMBER, 1932
tinguishers, consisting generally of sheet-metal tubes filled with mixtures of bicarbonate of soda and other materials in powder form, have been widely advertised, the Inspection Department has to report that, in its opinion, all forms of dry-powder fire extinguishers are inferior for general use, that attempts to extinguish fires with them may cause delay in the use of water and other approved extinguishing agents, and therefore their introduction is discouraged." Literature Cited JONES AND PERROTT."Extinction of Methane Flames by Dichloro-Difluoro Methane," U. S. Bureau of Mines. R. I . 3042. s, on Workers of Air Conditions," U. S Bureau of Mincs. I . C. 0439. ( 2 ) S ~ ~ a n"Effect ( ) RAMBONSEK,"Industrial Poisoning from Fumes. Gases, and Poisons of ManuM. LFGGE. Edward Arnold.London, facturing Professes." Translated by THOMAS 1913, p. 200. ( )
SOME ELEMENTARY LABORATORY PRECAUTIONS AGAINST
FIRE
Prevention is better than cure. Preventive measures fall into two chief classes: (1) those designed to avoid the outbreak of fires, and (2) those designed to minimize the effects of fires which may break out. I n the former class obvious details of laboratory technic rank high. Avoid handling volatile or combustible chemicals near open flamer. Heat volatile or combustible liquids only in a bath or on a hot plat-never over a direct flame. I n distilling such liquids, collect in a stoppered filter flask with a tube leading from the side-arm to hood, running drain, or outside air. Inspect all student set-ups before they are placed in operation. Insist that all active chemicals be disposed of in suitable ways. The waste jar is no place for them. In the second class, storage of chemicals is highly important. Volatile, combustible, and explosive chemicals should be as remote as possible from working spaces or electrical equipment where fire might conceivably break out. (Incidentally good light should be available so that there is no temptation to strike a match to read labels.). Juxtaposition . of individually harmless chemicals dangerous in combination should be avoided. Fire-fighting - apparatus should be conspicuously available and should include faamtype equipment. Prominent placards should designate the class of fire for which each particular type of apparatus is suitable. In the excitement attending a fire these would probably not be read but students will already know their general content and may retain sufficient presence of mind to seize the proper one in an emergency. Do not use carbon tetrachloride on alkali-metal fires. A few sand-buckets constitute an admirable supplement to conventional fire-fighting equipment. Keeg cool1 ~~
