Document KGmz14kV1jZaZrw15M0XDwdJo

NTHKNAI, COKKUSI'ONDKNCK May 4, 1964 I-KOM THOMAS B. BONNEY PITTSBURGH OFFICE To INDUSTRIAL HYGIENE COMMITTEE CHAIRMEN -yK-gj 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 3 ~3<f 7sP~p . QQjj ft'h Category Coe APC 004272 To Industrial Hygiene Comniitlec o*rt Chairmen May 4, l`^G4 Shut no. 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 rritant 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 L>ead, 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, ARL F. H. lllig, Pgh. M. O. Colwell, L. V. Cralley, file APC 004273 Industrial Hygiene Committee Chairmen ,f K. w. Perry Bauxite A1 w. L. Mowe /V. )S. T. ft-.W. V.M .Williams Mobile Alcoa Fab Alcoa Sm. N. A. Hayes Badin W. S. Barr Massena O. L. Royer C. O. Turner Pt. Comf. Sm. P t. 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 w. c. Harvey Cressona Davenport --w, e. 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 004274 Division Raw Materials Refining Smelting Fabricating Foundry ARL Alcoa Bldg. Plant Doctors Fehi.-,. 19<*4 x. S'? Works Doctor Bauxite Rosiclare Bauxite Mobile Pt. Comfort James Bethel John R. Duffey ------------------- . Howard Walker, Jr. John Griffin Alcoa W. N. Dawson Ptvwlan. Badin______________________A. F. Lapsley_________ Oi'urlle JaoU Punca-n Massena__________________Maurice J. Elder Rockdale J. T. Richards Vancouver F. J. O'Hara Warrick Thomas C. Burger Wenatchee_______________L., C. Miller____________ Alcoa -Wv-H, Chillicothe Cressona_________ Davenport________ Charles N. Hoyt Ralph Lyons A.W.Shafer Edgewater________ Lafayette ~ Lancaster________ Massena________ New Kensington Richmond Vancouver________ jpow e Chicago___________ Cleveland________ Detroit Edison ~ Vernon ________ Carl C. Kessler WUtUiu Colin Kamperman Ralph W. Dreyer M * Do > * * * k Ralph P. White w. A. Engel A. J. Szmiqiel Malcolm Dunham Victor H. Barbour" E. St. Louis New Kensington D. A. Fusia, Jr. Pittsburgh * = duplication APC 004275