Document pm7O69V8vjbwY510N4rJ1w6gw

1NT1CRNAT, ('OR RHSI*(ND1CNCK May 4, 1964 Kuom THOMAS B. BONNEY PITTSBURGH OFFICE To INDUSTRIAL HYGIENE COMMITTEE CHAIRMEN '-- f- RE: INDUSTRIAL HYGIENE NEWSLETTER SAWING MARINITE In recent months several incidents have occurred that prompted us to take a closer look at the potential problems associated with the sawing of Marinite. In the past, because of erroneous information given us about the composition of this material, we may have advised you poorly about the proper handling of it. In order to correct this, especially in view of the widespread use of Marinite, we felt that this Newsletter would be timely and appropriate. Marinite is an insulating refractory board manufactured by. Johns-Mansville. It consists of a mixture of asbestos fibers and diatomaceous earth bonded with an epoxy resin. In Alcoa it is widely used for headers in DC Casting Units and for trough linings. In order to be used for these applications, it is necessary that the Marinite first be sawed into appropriate sizes and shapes. Sawing generates a considerable amount of dust which is the main, if not the sole, cause of difficulty in handling this material. Were it not for the presence of the epoxy binder, proper control would consist simply of keeping the sawyers' time-weighted exposures below 5 mppcf, the threshold limit value for asbestos. However, the epoxy binder complicates the picture. Although the surface of a cured epoxy resin system is almost completely inert, this is not true of the interior structure which contains an appreciable amount of unreacted resin and hardener. As a result, dusts from machining and sawing epoxy resin systems are likely to be quite irritating. Dermatitis from APC 001242 To. Industrial Hveiene Committee n.r. Chairmen May 4, 1964SMltT l these dusts is quite common. They may also cause asthmatic-like reactions in certain sensitive individuals. (We have already experienced this in our Company.) Because active components of epoxy resin systems are present in them, dusts from Marinite cannot be treated as mineral dusts. Additional precautions are necessary, and the saw should be equipped with exhaust ventilation. (This is in accord with the recommendations of Johns-Mansville..) Probably most of the fabricating plants will require this type of set up. Respiratory protection is no substitute for exhaust ventilation, except at locations where cutting Marinite is an unusual, infrequent, and brief occurrence. Sawyers should wear long sleeved shirts to protect their arms from the irritant dust. Personal cleanliness is also important and the men should be instructed to wash up following their exposure to Marinite dust. If any of the recipients have any specific questions or comments con cerning Marinite, we will be pleased to hear from them. The latest of the Hygienic Guides are enclosed: Acrolein, Aluminum, Ethylene Glycol Monoethyl Ether, Manganese, Petroleum Naphtha, Pyridine, Tetraethyl Eead, Allyl Alcohol, Allyl Chloride, Cyclohexane, Ethyl Chloride, and Triorthocresylphosphate. Thomas B. Bonney TBB/mje Enclosures cc/encl: Company physicians G. H. Farrah, J. M. Plunkett, ARE F H. Illig, Pgh. (^M. O. Colwell, L. V. Cralley. file APC 001243 Industrial Hygiene Committee Chairmen $ K. W. Perry Bauxite Al. W. L. Mowe tf. VS. t/ii/tt.* ----- . W.V.M.Williams Mobile Alcoa Fab Alcoa Sm. N. A. Hayes Bad in W. S. Barr Massena 0. L. Royer C. 0. Turner Pt. Comf. Sm. Pt. Comf. Ref. H. A. Semken Rockdale E. B. Porter Vancouver R. L. Parsons Warrick G. D. Bruno Wenatchee A. J. Kukla Chicago D. J. Levin Cleveland W. M. Harris Cressona W. C. Harvey Davenport v-C. -Seipp ----- Detroit--- A. M. Miller Edgewater J. W. Foulke Edison L. S. Chambers Lafayette Arthur Hartwell Lancaster C. L. Bissonette N.K. R. E. Hospes Richmond T. I. McClintock Vernon 5/4/64 APC 001244 Division Raw Materials Refining Smelting Fabricating Foundry ARL Alcoa Bldg Plant Doctors Works Bauxite Rosiclare Bauxite Mobile Pt. Comfort Alcoa Badin Massena Pt. Comfort Rockdale Vancouver Warrick Wenatchee Alcoa Chillicothe Cressona Davenport Edgewater Lafayette Lancaster Massena New Kensington Richmond Vancouver CotrC Chicago Cleveland Detroit Edison Vernon E. St. Louis New Kensington Pittsburah Doctor James Bethel John R. Duffey - - -- Howard Walker, Jr. John Griffin W. N. Dawson A. F. Lapsley Maurice J. Elder J. T. Richards F. J. O'Hara Thomas C. Burger L.. C. Miller file wen Charles N. Hoyt Ralph Lyons A. W. Shafer Joseph Ferrante Carl C. Kessler 11 i mr Colin Kamperman Ralph W. Dreyer Ralph P. White W. A. Engel A. J. Szmiaiel Malcolm Dunham Victor H. Barbour Jr. * = duplication APC 001245