Theatre Catalog (1946-47)

Hand Fire Extinguishers for Theatre Use The How, Why of Fire-Fighting Equipment Are Summarized, with Notes on Servicing The theatre is crowded. The audience is auietly watching the picture unfold on the screen. Everything seems as usual, but— : In the basement, the large electric motor that operates the air-conditioning system becomes over-heated. Someone failed to give it the proper lubrication and care, and its heavy load causes the bearings to become very hot. Suddenly the whole motor bursts into flame. The fire spreads rapidly. If it reaches the stairway, and smoke is seen by the audience, mass panic may ensue. A workman near by, seeing what has nappened, dashes over and pulls the main control switch, and then takes down the carbon-dioxide fire extinguisher hanging there and quickly presses the valve. A cold blanket of carbon dioxide shoots from the extinguisher horn, smothering the fire speedily without harm to the motor. All this happened in a moment’s time, without any of the people upstairs even becoming aware of the fire. Yet had the workman failed to act quickly, or had he failed to shut off the power, or had he grabbed the wrong kind of extinguisher, tragedy might have occurred. The carbon-dioxide extinguisher, being a nonconductor, was safe to use on electrical fires such as this one, but the use of a soda-acid or foam extinguisher instead might have resulted in electrocution for the workman. And, of course, pulling the main-line switch was a double pro TYPICAL OF FIRE APPARATUS provided by up-and-coming communities for fighting fires is this Ward-LaFrance triple combination pumper. Among the features of especial value are the full-powered, six-cylinder, fire-truck engine, the accurate steering and short-turn radius, the heavy-duty frame, r | pump, an adequate booster tank, and the fully automatic clutch operation with 1946-47 THEATRE CATALOG the two-stage centrifugal tection against electric shock and a guard against the rekindling of the fire. This incident serves to illustrate what constitutes adequate fire-fighting equipment for all theatres: enough of the right extinguishers in the right places—and personnel trained in their use and operation. CLASSES OF FIRES Fire depends on three factors: (1) a substance which will burn; (2) enough heat to make it burn; and (3) enough oxygen to support the combustion. Re This article has been prepared from specially submitted material and from other authoritative sources. Special editorial thanks and appreciation are acknowledged to the following for cooperation on teat, pictorial material, and critical review: Robert S. Moulton and the National Fire Prevention Association; E. F. Tabisz and the Underwriters’ Laboratories, Inc.; Everett A. Warren and the General Detroit Corporation; W. P. Turnesa and Pressurelube, Inc.; J. A. Sargent and the Ansul Chemical Company; the Ward-LaFrance Truck Division of the Great American Industries, Inc.; and others, who, for reasons of their own, prefer anonymity. move any one of these three factors, and you just naturally put out the fire. A substance which will burn can sometimes be removed from a fire, but most fires have to be extinguished by reducing the heat or by cutting off the oxygen. To reduce heat, water or water-containing chemicals are used on fires. To cut off oxygen—which is the same as smothering—something that will keep air away from the fire has to be used. Whichever method is better—cooling or smothering—depends on what is burning. Therefore, in order to be able to choose the correct extinguisher for the various parts of the theatre, it is necessary to know something about the different kinds of fire itslf. There are three different classes of fires recognized by the National Board of Fire Underwriters, as follows: Class A fires, or incipient fires which occur in ordinary combustible materials, such as wood, textiles, or paper, and require the cooling effect of water or a water solution for extinguishment; Class B fires, which are incipient fires in small quantities of flammable liquids, such as oils, grease, and so forth, where a smothering or blanketing action is required; and Class C fires, or incipient fires in electrical equipment, where a non-conducting material is essential. Of course, there are some exceptions to these ru:es. For instance, if a per ground-position controls. Equipment of this calibre helps to keep down fire insurance rates, and the theatre man should insist that his local fire department be equipped wiih such modern, efficient fire-fighting appartus. But he should not forget the hand extinguishers are best for emergency fire fighting. (Photograph courtesy of the Ward-LaFrance Truck Division of Great American Industries, Inc.) 483