Document M4LNrE0m4KvkNR5jng71zkmGa

EXHIBIT DUP-729 E. !. cu Pont oe Nemours & Company Wilmington, Delaware ism EMPLOYEE RELATIONS DEPARTMENT HASKELL LABORATORY TOXICOLOGY ANO INDUSTRIAL MEDICINE on opiay App-icauiur: or a4,'. cc: Jasse Lieberr.ar., Chief, Occupational and F.adioio, Health Section City of Philadelphia September 2, 1970 Robert 0. Gorson, Professor of Medical Physics Stein Center Thomas Jefferson University 920 Chancellor St. Philadelphia, Pa. Dear Professor Corson: 33n connection with my dissent to the majority opinion of the members of the Ad Hoc Committee on Spray Application of Asbestos regarding the draft report that was discussed at the Fourth Meeting on August 31, 1970, you have asked that 1 sub mit a memorandum expressing my views. I wish to comment here with on the Specific Recommendation A: The Elimination, of Spray Asbestos Material (page 7), and on the preceding paragraphs, upon which the recommendation is based. Paragraph 5, pas* d points out that Rlt la difficult to ensure 100J5 containment of airborne asbestos material during the spraying operation." This was established as a fact by the testimony of Dr. Boucot after Yislting the site of Martin Luther King, Jr. School, and that of Mr. Wyman of General Building Contractors Association in a statement to the Committee, August 31, 1970. It is also a fact that neither the contractors nor any public health agency has put forth the Intense research effort that is required to overcome a problem such as this. Industrial hygiene engineering has succeeded in devising procedures for safely processing and using many potentially hazardous materials, such as beryllium, uranium ore, silica sand, lead, mercury, etc. Methods for spraying asbestos-containing insulating mate rial without emitting dangerous quantities of fibers from the site can most certainly be devised provided sufficient time and effort are expended by qualified engineering personnel. '409 CTTC* TMIHf.5 rO* OfTTCft L'V'NS . . . TmtOUGH CWtMiyTP' DUP.0901487 DU 022883 R. 0. Corson (Cont'd.) Page 2 September 2, 1970 Similarly, methods can be devised for the protection of persons spraying asbestos-containing insulating material and other persons working on the site during the spraying. An example of a precedent for the development of satisfactory safety procedures is afforded by sandblasting of metal parts in foundries, metallurgical establishments, shipyards, scrap yards, etc. It can now be done safely by using air-supplied helmets, enclosures and ventilation systems that have been developed for the purpose. Similarly, procedures and regulations can be devised to coat the sprayed insulation material and thereby prevent ero sion into air supply ducts. With respect to health protection during maintenance work, alteration of structures, or demoli tion of structures, the presence of sprayed-on asbestos- containing insulating material is only one part of the whole problem of -dust dissemination of asbestos products. These products may be encountered as pipe insulation, as interior and exterior structural board, and in floor tiles. The elimina tion of sprayed-on asbestos-insulating material would not eliminate the need for an awareness of hazard and practice of safe procedures in maintenance, alteration and demolition. CONCERN POR PIRE PROTECTION The use of sprayed-on asbestos-containing insulating material is intended to protect structural members of buildings from melting during accidental flras. It is intended to prevent serious or fatal collapses during the fighting of fires in office buildings, schools, hospitals, and hotels. The Committee should offer no recommendation which would interfere with or hinder adequate protection of the structure from fire. A pro hibition of the use of asbestos-containing material at this time would leave as an alternative the use of a single material. Although this material was reported to the Committee to have been approved by the Underwriters1 Laboratories following a series of laboratory tests of effectiveness, the fact remains that the building construction industry has not had an oppor tunity to use and to test it on a long-term basis with respect to its performance. This concern for adequate protection of structures in ease of fire indicates that the construction industry should have some alternative in the event the sub stitute asbestos-free material should fall, either with respect to performance, or adequacy of supply. DUP 0901488 DU 022884 It. 0. Corson (Cont'd.) Page 3 September 2, 1970 Page 6, Paragraph 9 I choose to withhold at this time an active dissent from the draft statement that "it is prudent for public health officials to assume that there is no level of concentration of airborne asbestos fibers below which adverse effects will r.ot occur in population groups chronically exposed." There v/as evidence furnished to the Committee that asbestos fibers, like every other toxic agent, can be tolerated at some level greater than aero concentration without adverse response. Reference may be made to the reprint entitled "Asbestos and Health in IS69," which was furnished to the Committee members. Zt is by George W. Wright and appeared in the AMERICAN REVIEW OP RESPIRATORY DISEASE, Vol. 100, No. 4, pp. 467-479, October 1969. There is definitely no occasion for dissent from the statement which follows the above: "the committee endorses the consensus of many experts that every reasonable method should be exercised to limit the discharge of asbestos fibers into the environment from all sources." SPECIAL RECOMMENDATIONS: A. ELIMINATION OP SPRAY ASBESTOS MATERIAL Acceptance of the statements made above would argue for the addition, following parts 1 and 2 of this recommendation, of a statement similar to the following: "/unless the prospective prime contractor will furnish to the City of Philadelphia a detailed plan of procedure, acceptable to the City, whereby emissions beyond the site will be con trolled to the limits expressed in Recommendation C (2) and will give auurwci that a sealant coat will he applied over the insulating material on those surfaces which are to become a part of an air supply system." Thank you for this opportunity of adding these remarks concerning my dissent to the record. aVery truly yours. rJJames P. Morgan ' Consultant Industrial Hygiene JFM/rlm DUP 0901489 DU 022885