Document j402Xpj9yEnp4DqZ7GXGj6XN

UC 149 INTERNAL CORRESPONDENCE RECEIVED APR 1 1 1975 MINING AND METALS DIVISION To (Nam#) Division Copy to Mr. W. C. Thurber UCC Metals Division 38th Floor 270 Park Avenue New York, NY 10017 Messrs. R. E. Byrne, Jr. J. L. Myers File P. 0. BOX 579, NIAGARA FALLS, NEW YORK 14302 April 8, 1975 Originating Dept. tl Calidria" Asbestos Subject Backup Information - Marks Bill Discussion The information package we discussed is attached. It is intended to answer the questions raised by Drs. Selikoff and Wright and to give you a comprehensive picture of the facts as we have them, uur available sanding and grinding data have also been added. When you have had a chance to review this, let us discuss what parts of it we may want to transmit to Senator Marks in writing. As the medical experts become involved, it is important to keep in mind that all of our tests are based on 0SHA fiber counts. All particles which meet the L/D >3 and L >5p criteria which, in the judgment of an experienced counter, could possibly be asbestos were counted as such. There is good evidence but not proof that many but not necessarily al1 of the particles reported as asbestos are glass chips or other extraneous "fibrous" particles. We can argue that in many cases the counts reported are too high but our supporting evidence at this time is a little weak to argue that they are generally zero. As you also know, we did not pursue the EM work and look for fibers shorter than 5u and resin particles with fibers sticking out. Our case is going to have to stand or fall on the OSHA procedure. Turning to specifics, each of the four tables submitted previously has been expanded to include area and background sample results. Some data on the spraying of gel coats containing no asbestos have also been added. Unfor tunately, the area type samples were generally obtained to provide exposure levels outside the "active" area to facilitate TWA estimates or to check against extraneous fibers being counted as asbestos. They usually shed little light on the duration of dust in the area. My own opinion is that we could possibly select some that are helpful but the total group adds little and detracts from clarity. Supplemental details for each set of tests are provided. Unfortunately, once past the wall and ceiling texture data, each test sequence was enough different to require separate treatment. This information is presented in approximately the following format: 1. Application details - commercial or simulated, and type of use. 2. Spraying details - gun type and how operated plus comments on occupational and environmental exposure. UCC 010043 Mr. W. C. Thurber -2- April 8, 1975 3. Finishing details - How the particular article is finished, i.e., sanded, ground or not abraded. Our data from field and laboratory tests is introduced as part of Table III on polyesters. We may want to put this together as a separate presentation. 4. Long-term exposure. The last item, long-term exposure, is easy to discuss but hard to define quantitatively. The approach taken is that the sanding and grinding data remove a substantial depth of material in a very short time. If the total fibers found is averaged over several years, the level should be indistinguish able from background. Overall, the discussion addresses all of the points you raised except the question of droplet size and persistence. With so many different liquids and spray types, I do not know how to get a handle on this quickly but will keep looking. We are awaiting word from A1 Harvey on their sanding data. They should be of some help on the wear question. The information from the AIA/NA on the Yale case is also enclosed. This looks very much like the situation in Laiitornia that was reported in great detail at the Industrial Hygiene conference in Miami last year. Asbestos is mixed with enough water to make a thick paste and it is sprayed onto a ceiling. The water evaporates, leaving a mat of essentially pure asbestos without any binder. The California people had great difficulty finding any fiber counts above background while Yale reports 18 fibers/cc. If you take an unbound asbestos mat and rub it hard enough, there is no reason to dis believe that a count this high could be obtained. The obvious point is that this is the extreme case of unbound asbestos and is just not relevant to the situation we are considering. I will let you know right away if any new information turns up. HBR:cjb Attachments H. B. Rhodes UCC 010044