SAFETY Dry Chemicals Tested on Fires in Vinyl Chloride and Napalm Fires in vinyl chloride can be extinguished effectively with dry chemical fire equipment, according to preliminary tests made by Ansul Chemical on its fire test field. Tests, made at request of a midwestern chemical company, indicate that vinyl chloride may have a fire intensity approximately three times greater than liquid propane under corresponding conditions of pressure and temperature. Because of this, Ansul engineers recommend that three to four times more dry chemical equipment b e used than that required to extinguish liquid propane fires. The engineers noted an unusual characteristic of vinyl chloride during the tests. W h e n liquid vinyl chloride was vaporized into the air, it vaporized completely. However, when the discharging liquid hit against an o b j e c t in this case a steel baffle plate—some liquid froze into a semisolid. This was thrown over the surrounding area by the velocity of die flames. Solid material burned slowly, like solid paraffin, but caused many points to reignite. Complete coverage of all parts of the
flame area with dry chemical was necessary. Ansul engineers note that vinyl chloride fires can be extinguished effectively with dry chemical equipment, but they strong])' recommend an intensive training course, in which actual vinyl chloride practice fires are extinguished, for all personnel coming into contact with the chemical. Napalm Gel. Dry chemical fire equipment has also been used to extinguish Napalm gel fires, according to Trygve Elmenhorst, Ansul distributor in Norway. Several small test fires were extinguished with a 30-lb. hand extinguisher; a final test was conducted on two wooden walls, each 12 X 18 ft., forming a corner, with a roof overhead and wooden shelves inside. Some 250 liters of Napalm were splashed over t h e structure. O n c e the fire was burning strongly it was extinguished in two minutes with a 350-lb. extinguisher.
• Bow's Midland Division improved its severity rate 85% in 1953; 1953 rate was 0.07 days lost per 1O0O hours. Accident frequency rate improved
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387c, declining to 1.33 lost-time accidents per million man-hours. Division has had no fatalities in more than two years; number of lost-time injuries fell to 27, from 42 in 1952. • Hanford Works' major injury frequency rate was 0.69 per million manhours in 1953, compared with 0.85 in 1952. (Nationa! Safety Council figure for the chemical industry is 5.10). Total number of injuries was reduced by 372 from t h e 1952 figures. Severity was 0.028 per 1000 hours. • Blow Knox's chemical plants division wins first place in 1953 National Accident Prevention Contest of Associated General Contractors of America. Award recognizes best safety record among contractors doing more than 500,000 man-hours annually. During 1953, division did more than 15 million man-hours of construction work. • A booklet titled "Foam Fire Protection" is available free on request to National Foam System, West Chester, Pa. Designed for quick reading and easy reference, it contains basic information relating to mechanical and chemical foam and their devices.
Plastic Panes Release Pressure From Explosions Quickly Windows of this building at Emery Industries are made of panes of Tenite. In case of a blast, flexible panes pull away from casings, to effect a quick release of pressure. Release is so fast that sufficient pressure to blow out walls or window frames cannot build up. Galvanized strips are crimped on edges to add rigidity and facilitate installation
RESINS and OILS for Rubber Processing You will find Neville Coumarone Resins ideal extender-plasticizers, which will not tend to lower hardness, tensile, modulus or tear. They are available in various grades of melting points and colors, for use in making white wall tire stocks, tires and tubes, rubber mats, wire insulation, mechanical goods, etc. Neville Resins and Oils are products of years of experience in meeting rubber processing problems, saving production time and costs, and improving product quality.
> I T T S B U R G H 4 5 , PA. Plants at Neville Island, Va., onar C.4-R
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