Document RJbkza81rvDNQ8BG3aqeJK1Gk

GRACE Construction Produi r vivwon W.R. Groce 4 Co. 6300 Button Gwinnett Drive P. O. Box 620009 Atlanta. GA`30362 Tel. 404-448-5880 February 6, 1987 Mr. James Coleman Bonitz Insulation Co. of Georgia P. O. Box 22398 Savannah, GA 31403 Dear Jimmy: Enclosed is the letter concerning wetted SCA-12 and NVS-38. As I mentioned, the only plant you would have dealings with on this material is our Irondale facility. If I can be of further help, let me know. JCH/ds Enclosure cc: Franklin Arnold 15192899 I GRADE Construction Products Division W.R. Groce & Co. 62 Whittemore Avenue Cambridge, Moss 02140 16171 876-1400 December 1, 1986 In the next few weeks you may notice a slight change in the appearance of Zonolite Concrete Aggregate and NVS. About the middle of December we will begin to dampen, with water. Aggregate made from Libby ore concentrates. This is being done so that users of Zonolite Aggregate products will comply with a new Occupational Safety and Health Agency (OSHA) standard which will become effec tive January 15, 1987. Vermiculite deposits around the world are located near or with asbestiform minerals. These deposits are often co-mingled. The mill beneficiation and plant exfoliation processes for vermiculite remove all but trace amounts of asbestos from the finished product. As indicated in Material Safety Data Sheets previously sent to you, Aggregate made from Libby ore concentrates contains a trace contaminant called tremolite. Tremolite is a form of asbestos and employee exposure to it is regulated by Part 1910 of the OSHA standard. The new standard establishes a permissible employee exposure level of 0.2 fiber per cubic centimeter (f/cc) of air as an eight hour time-weighted average (8-hour TWA) and an action level of 0.1 f/cc as an 8-hour TWA. For airborne concentrations in excess of 0.2 f/cc, the standard requires the employer to take a number of actions to protect the health of its employees. For exposures in excess of 0.1 f/cc, the standard requires the employer to conduct exposure monitoring, institute training and employee medical surveillance programs. v For exposure levels below 0.1 f/cc, no action is required. For most uses of Zonolite Aggregate products, time weighted average exposure levels will be below 0.1 f/cc. It is our objective to supply you with a material which does not exceed the action level. 15192900 2- - Grace has collected, and is continuing to collect, objective data which, to date,' demonstrates that the addition'of water to vehniculite can control airborne fiber concentrations below the action level. OSHA will allow employers to use such objective data to show that their employees will not be exposed above the action level as a result of using this product. Subsequent provisions of the regulation do not apply where it has been determined that exposures are below the action level as indicated by the objective data collected by Grace. Information regarding the objective data is available upon request. A new bag is being used that is lined with polyurethane coated paper which improves the flow ability of the aggregate. The new bag is also a tear top bag. The tops of each bag can easily be torn off by the worker thus facilitating pouring of the aggregate out of the bag top. This feature eliminates the need for further cutting of the bag and shaking it in order to get all vermiculite out. Please encourage your workers to use this feature. Because the new packaging for dampened material is slightly larger than that to which you have become accustomed, the bags may appear less full and heavier. The bag contain ing ZCA will weigh approximately 40 pounds and the NVS bag 46 pounds. However, material is being placed in the bags so you will see no difference in yield per 4 cubic foot. We believe you will find the dampened material easier to handle and it will not affect performance. If you have any questions with regard to this change, please contact your regional office. Sincerely, HTD:cm / '- H. T. Dudley Group Product Manager L 15192902