Document jaa4Vedw9VDonye7JeMV0jk5

B. K, Bryant 701-210 INDUSTRIAL HYGIENE MEMORANDUM PLAINTIFF'S EXHIBIT UC-3716 To: SID Supervisors (938) R&D Supervisors Services Supervisors Mr. H. L. Robinson From: Fred Williams January 24, 1972 increasing concern about asbestos has resulted in the issuance of an emergency standard that reduces the concentration cf airborne asbestos dust to which personnel may be exposed without approved respiratory protection. This standard became effective December 7, 1971, as reported in the Federal Register, Chapter XVIi, Part 1910 - Occupational Safety and Health Standards. Section 1910.93a Asbestos dust states: (a) The 8-hour time-//eighted average airborne concentration of asbestos dust to which employees are exposed shall not exceed 5 fibers per milliliter greater than 5 microns in length, as deter mined by the membrance filter method at 400-450 X magnification {4 millimeter objective) phase contrast illumination. Concentra tions above 5 fibers per milliliter but, not to exceed 1(3 fibers per milliliter, may be permitted up to a total of 35 minutes in an hour for up to 5 hours in an 8~hour day, (b) Engineering methods, such as but not iimited to, enclosure, vacuum sweeping, and local exhaust ventilation, shall be used to meet the exposure limits prescribed in paragraph (o) of this section. Where such engineering methods are not feasible, or do not other wise reduce the concentrations below those prescribed in paragraph (a) of this section, respiratory protective devices shall be provided and used in accordance with paragraph (c) of the Federal Register. (d) (2) All hand - or power-operated tools which produce asbestos dust such as, but not limited to, saws, scorers, abrasive wheels, and drills shall be provided with local exhaust ventilation and dust collectors in accordance with the American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems; ANSI 2.9.2 - 1971. (d) (3) Employees exposed to the spraying of asbestos or the demolition of pipes, structures, or equipment covered or insuioted with asbestos shall be provided with respiratory protective devices in accordance with paragraph (c) (4) of the Federal Register. UCC 011895 _ - jL " <e) Asbestos cement, mortar, coatings, grout, and plaster shall be mixed in closed bags or other containers. (f) Asbestos waste and scrap shall be collected and disposed of in sealed baas or other containers. (g) All cleanup of asbestos dust and blowing shall be performed by vacuum cleaners. No dry sweeping shall be performed. In order to protect individuals working with asbestos and tc assure compliance with the Occupational Safety and Health Act, the following is recommended: 1. Notify the industrial hygienist when work with asbestos is to be performed that can create a dust, eg: sawing, grinding, blending, demolition, etc. (a) Air samples may be collected to evaluate potential personnel exposures to asbestos. (b) An evaluation will be made on the extent and type of personnel protection that will be needed. (c) Waste disposal arrangements can be made. (d) Record of personnel working with asbestos can be maintained. 2. When possible, substitute an insulation containing no asbestos. F, Will iams/ebc \ Industrial Hygienist UCC 011896