S T A T U T O R Y REQUIREMENTS FQR F L A M E R E S l S T A N C E IN T E X T I L E S GEORGE S. BUCK, JR. National Cotton Council of America, Washington 6, U. C. All cellulosic fibers are combustible. The ease with which textile fabrics made from these fibers ignite and their manner of burning differ widely, but the differences are the result of their fabricated form as cloth structure rather than of differences in the combustibility of the fibers themselves. In certain uses, a fabric having any degree of combustibility may be a fire hazard, whereas in other
uses only fabrics that burn with unusual rapidity or volume of flame could be considered potentially dangerous. In order to provide the greatest possible safety against fires, statutory restrictions upon the use of combustible textiles require flame-resistant properties in some applications and place limitations on the maximum rate of burning in others.
NDOUBTEDLY the statutory regulations which today require flame-resistant properties in textiles stem directly from serious fire accidents, generally those in which a number of lives have been lost. The Cocoanut Grove Law of the state of Kew Hampshire is the direct result of the terrible fire in the Cocoanut Grove Nightclub in Boston in which 489 persons died. After the tragic fire of the Ringling circus tent in Hartford, Conn., a number of states and a great many cities and towns adopted regulations which required all amusement tents to be durably finished for flame resistance. Even the sweeping California regulations, t,he only ones to include restrictions on fabrics for clothing use, stem largely from well publicized fire accidents, in this case the deaths of a number of children by the accident,al ignition of the rayon pile cowboy trousers which they were wearing. The forms which textile flammability regulations have taken differ materially in t,he various states and cities in which they have been adopted. There are, however, indications that the scope and coverage of municipal ordnances or st,ate l a w are falling into a more standardized pattern. An ordnance ( 2 ) reconimended by the National Board of Fire Underivrit,ers typifies a form of regulation n-hich most legislative bodies are now incorporating in t8heirlaws.
strictions on the use of combustible textiles in public places hrts been the unsuit,ability of flame-resistant finishes. The problem of defining a rate of burning or degree of fabric flammability which shall be considered hazardous is much more difficult than that of requiring flame resistance in textiles for specific applications. In the lattel; case, it is possible to make tests Tyhich show that a fabric either docs or does not carry a flame. A simple test using a match or candle generally gives the answer as readily as a more elaborate and refined test. When rate of burning is to be the criterion of safety, however, the first presumption necessarily allows for a rate of burning or degree of flammability that is considered safe. Obviously this is a necessity, because 75 to 80% of all our textiles are cellulosic and therefore combustible. These fabrics have been used for centuries, and it is inconceivable that their use should be outlawed, at least until the science of applying flame-resistant finishes has progressed far beyond its present stage of development. Therefore, the mholc problem of control of fabrics which burn in a presumedly dangerous manner depends on a realist’ic definition of a rtLte and manner of burning which are termed hazardous, and a measuring means by which “hazardous” fabrics can be distinguished from “safe” fabrics.
2. Decorative filaterials. ( a ) All combustible decorative material, including curtains, acoustical materials, streamers, cloth, cotton batting, st’raw,vines, leaves, trees, and moss, but not ineluding floor coverings, shall be rendered flameproof; provided this shall not be required of materials not exceeding one-sixteenth inch in thickness applied directly to and adhering to a noncombustible base. Such flameproofing, unless certified by Underwriters’ Laboratories, Inc. , or other laboratories of recognized standing, as being of a permanent nature, shall be tested by the f r e department each six months and the treatment renewed if necessary. ( b ) The use of imitation leather (or other material) consisting of or coated with a pyroxylin base is prohibited.
CALIFORNIA REGULATIONS
The first attempt t o govern the sa10 of textile fabrics or garments deemed hazardous was made in California in 1945 The original bill passed by the legislature of that state defined as hazardous “any article of wearing apparel, clothing, drapery, or other fabric or material made from or containing any synthetic fiber which is wholly or in part made from or contains any hazardous explosive or other substance in sufficient quantity so as to make such a fabric or material more highly flammable than cotton cloth in its natural state,” and made it unlawful to manufacture or sell such articles. The shortcomings of this definition were recognized later that year, and the California assembly revised it to read: ‘(any article made from or containing natural or synthetic fiber and determined by the Fire Marshal to be so highly inflammable [sic]as to constitute a dangerous risk of fire and hazard of injury to persons and property, taking into consideration the use or uses for which the article is made and designed to serve.” The lack of any suitable yardstick by which flammability could be measured or hazard defined was also recognized by the California legislature in the following section of this revised law:
“Place of assembly” is defined differently in each area of enforcement, but usually refers to a room or enclosure in which 50 to 100 or more persons gather for “religious, recreational, political, social, educational, or amusement purposes or for the consumption of food or drink.” Approximately 28 states and nearly three in every four of our larger cities have now in force regulations which in some degree conforin to this recommended ordnance. Five states formulated or broadened controls during 1949, and there is every indication that this trend will continue. The availability of more economical and more satisfactory flame-resistant finishes for textiles will accelerate this movement, for the principal objection to re-
I t is not feasible by statute to prescribe more specific tests than those herein prescribed [above], for it would appear that none have yet been fully developed. It is necessary, therefore, to com428
42 9
INDUSTRIAL AND ENGINEERING CHEMISTRY
March 1950
mit to the State Fire Marshal the conduct of research in these matters, and the development of tests for these materials, and the administration of the provisions of this chapter for the prevention of the risks and the avoidance of the hazards described.
*
The California Fire Marshal adopted as his test method the 45”flammability tester developed by a committee of the American Association of Textile Chemists and Colorists. This instrument utilizes a 6 X 2 inch strip of fabric and a standard 1-second ignition of the fabric surface with a hypodermic-type gas flame. Those samples over which the flame travels a distance of 5 inches in less than 5 seconds are termed “hazardous,” and those taking more than 6 seconds to burn 5 inches are classificd as “safe.” Originally four in the were ‘lasses Of California restrictions: Group 1. Dile fabrics ‘ Group 2. Group 3. Group 4.
Figure 1.
Burning Rates of Chenille Fabrics
Each lettered circle represents average burning rate of 10 strips as measured in laboratory indicated. Heavy line at 6 seconds is arbitrary division between safe and hazardous fabrics. This seven-laboratory correlation test employed the A.A.T.C.C. 45’ tester, but other testing instruments have shown similar results.
Napped, brushed, and Sized and coated fabrics Nets, sheers, laces, etc. Miscellaneous articles, including buttons
The application of the law to groups 3 and 4 was subsequently suspended pending further study, so that only fabrics in groups 1 and 2 fall under the California restrictions at this time. In several bills introduced into the U. S. Congress in the period 1945 to 1949, both the 45 O flammability tester and the horizontal flammability tester developed by the Fire Protection Section of the National Bureau of Standards were referred to as a means for defining dangerous flammability, Only in 1947 did any of the bills reach committee hearings, and after a review by the Interstate and Foreign Commerce Committee of the House of Representatives in March 1947, no further action was taken. I t was be-
Figure 2.
coming increasingly evident that neither the 45 method of measuring flammability nor the horizontal burning method could determine rate of burning reproducibly when used in a number of laboratories. Even more important, it has now become apparent that simple rate-of-burning measurements provide insufficient information for classifying flammability, because ease of ignition and volume and intensity of flame have an important influence on any potential hazard inherent in a textile fabric. During the past 3 years several interlaboratory testing programs have been carried out under the auspices of an industry committee of the National Bureau of Standards (I). The 45” flammability tester and the horizontal tester were both employed in these interlaboratory programs. The results of this extensive testing clearly demonstrate the need for further improvement in testing methods (Figures 1 and 2 ) . To meet the need for a better understanding of tensile flammability and for an improved method of measuring this property of fabrics, research fellowship has been established at Lowell Institute under the guidance of the A.a.T.F.C. Committee on Flammability of Consumer Fabrics. This fellowship has been supported in part by the American Association of Textile Chemists and Colorists, and lately by a $5000 fund, of which $2000 was subscribed by cotton textile mills, $2000 by rayon producers, and $1000 by retailers. The study, besides entailing the design or modification of a suitable testing device, will necessarily consider the follo~ving factors which significantly influence the flammability or fire resistance of a textile fabric :
Burning Rates of Napped and Brushed Fabrics
Results of two seven-laboratory correlation tests, using A.A.T.C.C. 4S0 tester. Interlaboratory agreement is good o n samples 10 and 11, but these samples are not necessarily dangerous, because volume of flame is small.
O
1. The fiber or fibers-cellulosic (combustible), noncellulosic (conrbustible), incombustible, and blends 2. Fabric construction-spun or filament, twist, weave type, and mechanical finishing 3. Chemical finishes, including dyes 4. Flame- or fire-resistant finish 5 . Humidity (ambient) and moisture content of sample
430
INDUSTRIAL AND ENGINEERING CHEMISTRY
6. Temperaturein burning cabinet 7. Preparation, handling, and past history of sample 8. Variations in operating technique, flame size, speed of operations, and direction of burning
Statutory requirements fer flame-resistant textiles in specific uses have created markets for fabrics processed with flameresistant finishes, but laws requiring limited flammability in fabrics have not significantly influenced the market for flamcresistant fabrics up to this time; the only regulation of this type is that of the state of California. Moreover, it is doubtful that this form of restriction will ever create a sizable market for flameresistant textile finishes, even if such regulations eventually prove
Vol. 42, No. 3
workable. The real market for flame-resistant textiles lies in those fabric uses now considered hazardous under existing types of municipal and state laws. The trend toward broader coverage by these laws, and their wider acceptance, will be accelerated by developments in chemical and finishing technology through which better and cheaper flame-resistant finishes are made available. LITERATURE CITED
(1) Buck, G. S., Jr., Am. Dyestuf Reptr., 38, 7 8 (January 1949). ( 2 ) IIatl. Board of Fire Underwiiters, “01dnance Providing f o r Safety to Life in Places of Asuemhly,” Section 2. iiEcsIvcDSeptember 26, 1949
FIRE-RETARDANT T XTILES A G O N S U ER S T A N D P O I N T KENNETH H. BARNARD Textile Resin Department, American Cyanamid Company, Bound Brook, N. J.
T
HERE is only one good reason for a consumer’s interest in &+retardant textiles, and that is his personal safety. Firehazardous clothing may cause him injury or even death. The possibility of such a fire may seem remote to the reader, but it seemed equally remote to 7000 people one sunny afternoon in Hartford, on July 6, 1944, sitting in a tent watching the clowns and the animals do their tricks. Maybe it was a cigaret butt in the dust-dry grass near the main entrance or a match tossed in the corner of the side wall, but whatever the initial cause the paraffin-soaked canvas wm quickly ablaze and with a great swish of smoke and flames the whole tent was a roaring funeral pyre for 163 people, mostly women and children. The greatest show on earth had a million dollars north of claims to settle, and five of its top executives were indicted for manslaughter, but no fineq, damages, or prison sentences can make up for the irreparable low of life, all of which could have been prcmnted by any one of scvera1 fire-retardant treatments. COCOANUT GROVE DISASTER
The reason for fire-retardant treatments on textiles was brought close to lo00 people who were celebrating the results of a Boston College-Holy Cross football game in a nightclub in Boston on November 28, 1942. To simulate its tropical name of “Cocoanut Grove,” the place was equipped with artificial palm trees, false walls of artificial leather, and a suspended fabric ceiling. I t is thought that a bus boy trying to locate a broken light bulb lit a match and started the conflagration. The tiny flame spread quickly through the fabric decorations and balls of flame rolled along the ceiling from one room to another, so that in a short time 489 people seeking pleasure there ended by losing their lives in a frightful way. Again, this tragedy could have been picvented by a proper fire-retardant treatment of textiles. These catastrophes, especially frightful because so many people were involved, are no more poignant to those left behind than that of a small boy in a cowboy suit of brushed rayon who played with a bonfre near Washington, D. C., and lost his life. This tragedy happened at the time California TVM passing a law prohibiting fire-hazardous clothing. However, passing a law under the pressure of some headline disaster is not the final answer to our problem. What is needed is better enforcement of the present laws, which in turn depends
on educating the general public to the hazards involved, along the lines of other drives for safety. The safety campaign conducted in the schools and newspapers for more careful automobile driving, the elimination of the hazards of the Fourth of July firecrackers, and the life insurance companies’ broadcasts on health and disease are the type of campaigns really needed to rcduce accidents from hazardous textiles. FIRE-RETARDANT REQUIREMENTS
Assuming an interest in slow-burning textiles, either based on new l a m about to be passed or old ones t.hat are better undcrstood and enforced, what’ other characteristicx sbould such a textile have to interest the consumer? In general, unless it closely approximates all the characteristics of the goods before treatment, for fire retardancy, a textile will lose its original customers. To be salable, in addition to its fire-retardant properties it must meet the following requirements. Dermatitis. The treatment must not cause dermatitis if the textile is to be used for clothing or is to come in contact with the skin. This test is second nature to all reliable chemical companies interested in producing new finishes, but as it is expensive to perform, requiring a minimum of 200 individual patch tests, the average consumer depends on his supplier to make it for him. Almost equally bad, although not so damaging as dermatitis, is the possibility of the formation of a bad odor. This too is a problem of n-hich the chemical manufacturer is well aware. Tensile Strength. Many fire-retardant treatments are durable because there is a chemical rcaction between thc chemical applied and the cellulose. It is almost impossible for cellulose to react without being veakened, so that some loss in tensile strength is to be expected. If the loss can be held under lo%, there is no harm done. Unfortunately, with the litghtcr and more open goods such as lawns and voiles, the reaction is more severe, as more surface is exposed per unit weight and the loss in tensile strength is, thcrefore, greater. As light goods are n a t u r d y weaker goods originally, any loss at all becomes a serious matter. Some testing laboratories also make tensile strength tests on wet cloth. It has been observed that :I loss in wet tensile strength may indicate degradation of cellulose when dry tensile strength may be but little affected. The life of a treated fabric exposed to outdoor conditions would certainly be shortened if the
