Document 2MJbEXqxQm76KD1zLLZ5ZrEr

Mr. George M. Wilkening Head, Environmental Health and Safety Department Bell Laboratories 600 Mountain Avenue Murray Hill, New York 07974 So&CEbg S3 / -97 (' Fr.Oii: if. -1 u*r?a,' Ccjletf /ar:.'PSiVr*3o CEDungsy Dear Mr. Wilkening: This is in response to your letter of July 9, 1976, inquiring into the applicability of the present Occupational Safety and Health Administration (OSHA) standard for asbestos (29 CFR 1910.1001) where airborne asbestos concentrations inside office buildings are consistently less than those found in the outside community air. As you know, the Secretary's asbestos monitoring regulation at 29 CFR 1910.1001(f)(1) requires initial monitoring of "every place of employment where asbestos fibers are released." Such initial measurements of office building employee exposures to airborne asbestos are, we believe, required whenever there is any reason to believe that airborne asbestos is present inside the building regard less of whether the levels present are less than those generally found in the normal outside environment. Obviously, an employer's suspicion what airborne asbestos exists inside the building should be aroused whenever asbestos is worked or used anywhere within the building. Similarly, where asbestos has been applied to walls, ceilings, exposed structural steel, air ducts, plenums, return air spaces, boilers, pipes, etc., or where asbestos is being released into the atmosphere from someplace other than the employer's workplace such as an adjacent industrial operation, the employer should be alerted to the possi bility that asbestos fibers are present inside its building. SOL:WEBlasier(1/18/77)rjp Rm. S-4014 - Ext. 36802 i HER 0000912 Page 2 Although, by its express terms as well as the developing case lav;, 29 CFR 1910.1001 (j) v;ould require medical exam inations where employees are exposed to any concentration of asbestos fibers, it is current OSHA policy to require medical examinations only when employee exposures exceed 0.1 fibers greater than 5 microns in length per cubic centimeter (f/cc greater than 5 microns) on an 8-hour time weighted average (TWA) basis. Our policy in this regard derives support from a recent recommendation from the National Institute for Occupational Safety and Health (NIOSH) that the permissible exposure limit for airborne asbestos be fixed at this level. This recommendation was made by NIOSH in its document titled. Re-examination and Update of Information on the Health Effects of Occupational Exposure to Asbestos (December, 1976). Insofar as continuous monitoring is concerned, the standard (29 CFR 1910.1001(f)(2) and (3)) requires that after the initial determination, sampling "... shall be of such frequency and pattern as to represent with reasonable accuracy the levels of exposure of employees. In no case shall sampling be at intervals greater than 6 months for employees whose exposure to asbestos may reasonably be foreseen to exceed (2f/cc greater than 5 microns on an 8-hour TWA basis)." Where the initial measurements show asbestos concentrations to be far below this level, then further sampling normally need not be performed, until there is reasonable cause to believe that the airborne asbestos concentrations revealed by the initial measurements have changed. The initiation of such processes or the presence of such factors as those indicated in the second paragraph above should similarly cause an employer to question the current validity of initial determinations previously made. In closing, let me point out that I was somewhat surprised by the abestos concentrations found by you in the air outside your office buildings. As I am sure you are aware, the outside levels indicated in your letter are on the order HER 0000913 page 3 of 1 to 2 magnitudes higher than the environmental norms for most regions of the United States. Thus Bell's selfinitiated efforts to survey the environment both inside and outside of its office buildings are particularly significant as they suggest Bell's recognition of the serious hazards that have been associated0 with exposure to asbestos. I hope you will find this letter responsive to the questions you have raised. Sincerely, Morton Corn Assistant Secretary of Labor t HER 0000914