The Part Asbestos Plays in Fire Prevention
Nature Provides Certain Non-Burnable Materials Which Can be Used for Building Purposes—Advantages of Asbestos for Roof Covering—Importance of Interior Fireproofing
IT is unfortunate that in this free country of ours it is so often necessary to make laws to compel our citizens to do that which it is to their own best interests to do, both from their own personal viewpoint and in their relations with their fellow citizens. Finding, however, that in spite of the millions of dollars spent annually in this country to educate and assist property owners along the lines of fire prevention, that the use of inflammable, temporary and dangerous construction is still present to an extent that is in reality criminal, many cities and towns have adopted ordinances prohibiting this indiscriminate use of materials that are a constant menace to the entire community, as well as the property owners themselves. Idealism is, however, very apt to be wasted when actual results are being sought for and so perhaps the best way to induce the property owner to take the necessary precautions on behalf of his fellow citizens is to show him that by so doing he is at the same time advancing his own welfare. This can be done with very good effect by those who are recognized as exponents of fire safety: fire chiefs, fire insurance engineers, state fire marshals, industrial fire officials and other fire prevention officials. It is the plain duty of these men to educate propertyowners along the lines of property conservation, economics, and, most important of all, protection of the human life.
Nature has endowed us with certain materials that are impervious to the attacks of her own most rapacious marauder, fire, and the proper realization of the value and correct use of these materials will go a long way to reducing the tremendous dissipation of property values, then fire and the accompanying tragic, in most cases, unnecessary loss of human lives.
Nature Provides Non-Burnable Materials
One of the most remarkable and valuable of all natural materials, that is absolutely unchanged when subjected to flame and intense heat, is asbestos. This mineral, although mined in quarries in much the same manner as ordinary limestone, is in reality not a solid substance, but is fibrous in its structure. These fibres may be divided into smaller fibres and divided again, so that even the microscope cannot detect the eventual size. But it is not of asbestos that this article desires to concern itself, interesting though that most wonderful material may be. It is of the building products made from asbestos that we are at present concerned.
Building Material Made from Asbestos
Asbestos fibres (see Fig. 1) used in conjunction with Portland cement and compressed together with that material under a hydraulic pressure of 5,000 pounds per square inch, into various forms and shapes and laminated in layers up to any desired thickness, form a type of fireproof building materials that are deserving of deeper study and the constant recommendation of the fire engineer. Most everything is fire resisting, that is, it is not ignited the instant flame or heat is applied to it, but all materials that are merely fire-resisting will burn, many of them fiercely, when once ignited and for some of them the temperature, or intensity of heat, necessary to start the fire is too low to offer even temporary assistance to those engaged in checking the fire’s advance. Building materials. however, composed entirely of asbestos fibres and Portland cement cannot burn. The significance of this fact is apparent to all.
Wide Range of Fireproof Construction
Then consider the wide range of fireproof construction offered by the materials made in this way: asbestos shingles, in various styles, sizes and colors to conform to any type of structure and architecture, all of them fireproof; asbestos building lumber, made in thicknesses of 1/4-inch and up, and in practically any size sheets up to 48-inch widths and 96-inch lengths; asbestos wallboard, made in 3/16-inch thickness and in the same sizes as the asbestos building lumber; and asbestos corrugated sheets. The shingles are used to as good advantage on the sides as on the roofs of buildings. They are the best possible fireproofing, since not only do they cover the building with a material that cannot burn, but they are held together by copper storm rivets, so that they form a complete unit, or fireproof blanket. The illustration of the church at Bloomfield, N. J., that was devastated, due to the spark that settled on its “fire-resisting” roof (Fig 2), shows clearly how a really fireproof roof is necessary to protect any building from fire originating in outside sources. To confine the fire to the building in which it originates, a fireproof roof is essential since it not only prevents the flames from bursting through and spreading, but also does not furnish inflammable material which in the case of a burning roof causes firebrands and sparks to fly, with the resulting danger and damage to nearby properties. In this way conflagrations are caused, and Fig. 3 shows what happens when there are several such unprotected buildings adjacent to one another.
Roof and Walls Should Be Fireproof
The photograph of the school at Oneonta^ N. Y. (Fig. 4), on the other hand, shows well how a fire may entirely gut out the inside of a building and yet be held within the confines of that building by proper wall construction and an asbestos shingle roof.
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Asbestos building lumber is used for exterior panelling, producing the popular half timber effect and at the same time giving adequate fire protection. It is not. only necessary to have the roof fireproof to protect the building from fires originating outside, when the buildings are closely adjacent to one another, as is clearly seen in the photograph of the Rockaway Beach fire (Fig. 5).
Interior Fireproofing Also Important
Asbestos building lumber is also used in conjunction with asbestos wallboard for interior fireproofing. Good practice calls for the underlining of first floors in residences, over the cellar, the underlining of all floors in schools, hospitals and other public buildings, the underlining of all closed stairways, the interior sheathing of all closets and storage rooms, the wall paneling of all kitchens, heater rooms, power rooms, electrical apparatus compartments, elevator shafts, airways, etc., etc., with these materials which cannot burn themselves and afford the maximum fire protection in those parts where fires so often start or spread with resulting property loss and danger to life. There is shown in Fig. 6, showing the interior of a school building, the danger caused in not so fireproofing the floors and walls. This fire started in the basement and went right through to the roof, whereas it should have been held in the basement and easily smothered.
Advantages of Asbestos Corrugated Sheathing
Although all of the above mentioned fireproof asbestos materials are used extensively for industrial as well as residential and public buildings, there is a particularly valuable material used for roofing and siding industrial properties as well as barns, railway sheds, roundhouses, piers, warehouses, oil storage tanks, etc., etc. This material is asbestos corrugated sheathing, furnished in widths of 27 1/2 inches, with eleven complete corrugations to each sheet, and in lengths up to 120 inches. Applied directly on the steel purlins with aluminum bolts and tie wires, inserted through lead washers, asbestos corrugated sheathing leaves nothing to burn and presents an effectual check to the advance of fire. Fig. 7, showthe Luckenback Pier, illustrates the ever-present danger where long, open spaces, surrounded and filled with inflammable material are permitted to exist. Had this pier been constructed, as all piers should be constructed, with fire walls and of fireproof material the loss would have been prevented. An effectual method of fireproof construction for such properties is asbestos corrugated sheathing applied on steel purlins for siding and roof, firewalls of the same construction, transversely throughout the buildings’ length, and in the case of such piers a sheathing of asbestos lumber under the pier construction itself to prevent the ignition of the base structure through combustion of the gases and oils, floating on the surface of the water.
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From the very few out of the multitude of uses to which fireproof asbestos building materials may he put that are mentioned here, some idea of the value of their nature may be realized, and it is earnestly hoped that the great and admirable work of educating properly owners to their own responsibilities, where fireproof construction is concerned, may be somewhat assisted by these few brief suggestions.