Document 2qpj5zmNKYJOag3QL42nBBNXr

Gypsum 000167 * ;*** mJUi 10 J Association '-5"r.a. 201 North Wolto Shoot. Chicago MiOi July 9, 1968 ]PLAINTIFF'S EXHIBIT | WRG-47 9 Mr. M. Milton Glass, Chairman Board of Standards and Appeals City of New York 80 Lafayette Street New York, N. Y. 10013 SUBJECT: .c\ Dear Chairman Glass: Calendar No. 118-68-CR Having had an opportunity to study the proposed rule, as well as the transcript of the hearing of May 10, 1968, concerning the application and protection of spray-on asbestos fire proofing, the Gypsum Association would like to submit a few cosnents for your consideration. The Gypsum Association and our member companies do concur with Che Intent of the proposed rule. We are aware that similar situations have ezisen In other areas and that similar rules have been applied. We see no reason why cementitious type fireproofing materials should be In cluded in this ruling in that there id little similarity between cementitious ^and asbestos fibered materials. Cementitious materials are eomparitively bard setting materials, where asbestos sprayed fiber materials are soft. There Is no dust residue from the sprayed application of cementitious materials. This is the real problem of confining the dust residue from the spraying-on of asbestos fibered material. Most Important is that the density of cemen titious material Is predetermined in the dry goods and cannot be altered by the mechanic doing the spraying. If aproblem had been experienced with cementitious type materials, we are sure that they would have been Included by the Building Department in their comments. The only recommendation made to include cementitious type materials under this new rule was made by the president of the Spray Mineral Fibered Manufacturers' Association, lac., and therefore lb a little biased If not plain old fashioned "sour grapes". If, however, cementitious materials are to be Included in this proposed rule, one change should definitely be made. 2. Mr. M. Milton Glass, Chairman Board of Standards and Appeals New York, New York 5 501 lo Sub-paragraph "d" requires tamping to the required thickness. Tamping is often required with sprayed fiber fireproofing in order to achieve a re quired density. The tamping of plaster products, however, could cause bond failu:^ and should be prohibited when plaster products are being applied. Sub-paragraph "d" does not make mention of the required density which, in the case of sprayed-on fiber products, is of much greater importance with repect to fire protection than is its thickness. With this fact in mind, the Board may well want to consider enlarging this requirement to include the density requirements. We would also suggest that the dusting requirements such as those re quired by the General Services Administration in their "Spray Fire protection Specifications" should be contained in the new ruling. This step wouldgo a long way to eliminating the problem of having the fiber dust blowing about and dirtying the surrounding neighborhood buildings, autos and citizenry. This G.S.A. Specification calls for tests to be conducted with air velocities of not less than 800 fpm or 9 miles per hour, a safety factor of two would increase this to only 16 miles per hour, which seenu. harciy adequate for the high-rise buildings in New York City. The Board may also want to give serious consideration to including the re quirements of a "scratch test'' similar to chat which is required by the (bity and County of San Francisco, since displacement is of concern to the Board, particularly as it applies to such areas as garage, ceilings, etc. I am planning on being in attendance at the July 19, 1968, hearing concern ing this ruling and will be most happy to answer any questions the Board may have. Very truly yours, GYPSUM ASSOCIATION DEB:da D. E. Brackett Building Code Consultant cc: Mr. John Hovind, National Gypsum Co. Mr. L. A. Barron, Vermiculite Institute v;, t << ' * / S'* .< tv V / .t r