Timothy Fisher, CSP, ARM, CPEA
American Society of Safety Engineers
1800 East Oakton Street
Des Plaines, IL 60018-2187
Dear Mr. Fisher,
This letter is to acknowledge receipt of the correspondence from Mr. Frank Perry of December 13, 2004 concerning our Notice of Intent to Change the TLV for Hydrogen Sulfide.
Your information has been forwarded to the appropriate committee members on the Threshold Limit Values for Chemical Substances Committee for consideration.
I would like to comment on a few of the points you make concerning our TLV development process:
Page 2: “2. Solicit a call to the general public for papers and studies regarding this issue.” ACGIH has an extended time period when we solicit the public for information concerning the substances we are considering for either development or revision of a TLV. We accept input at any time concerning any substance. However, we specifically request scientific papers, studies, and comments from the public during the time when a substance is first placed on the Under Study list through the Notice of Intent to Change (NIC) period. Proposed values for Hydrogen sulfide have been on the NIC since 1998, a period of more than 5 years. Attached is a copy of our TLV/BEI Development Process which will explain the timing and details of our process.
Page 2: “3. Submit a request to the National Institute for Occupational Safety and Health (NIOSH) to conduct research regarding H 2 S exposure.” We are not a research organization and do not commission studies. We work within the limitations of the existing scientific literature. (See TLV/BEI Development Process)
Page 2: “4. After additional science and supporting data is obtained, revisit the issue and arrive at a consensus position.” ACGIH is not a consensus organization. The TLVs and BEIs represent a scientific opinion based on a review of existing peer-reviewed scientific literature by committees of experts in public health and related sciences. Attached is a copy of our Statement of Position, addressing the consensus issue in paragraph 4.
Page 2: “We also believe it appropriate to comment on the development process…” You note that our TLVs and BEIs are sometimes viewed as standards, particularly in instances where OSHA has no published PEL. ACGIH TLVs and BEIs are not developed for use as legal standards and ACGIH does not advocate their use as such. This position is clearly communicated in our Statement of Position, which is posted on the ACGIH website and contained in the TLV and BEI book. Our Statement of Position discusses the factors that make adoption of our TLVs and BEIs as standards problematic, especially in the areas regarding economic and technical feasibility, and availability of acceptable sampling and analytical methods. The TLVs and BEIs are guidelines, based solely on health factors.
Page 2: “Documentation of intended changes should be made available at reasonable cost on the CGIH web site.” When ACGIH proposes a change in a TLV or BEI, it is published on the NIC list in the TLV/BEI Book, in the Annual Report, and on the website for the membership. Draft Documentation for the NIC substances are available to the general public on the website at www.acgih.org/store at a cost of $50. For Hydrogen sulfide the product number is #7NIC-012.
Page 2: “Minutes of meetings and deliberations of meetings leading to revisions of TLVs should be posted on the ACGIH web site.” The vehicle that ACGIH uses to communicate the science/basis for a TLV is the Documentation . The Documentation is designed to be self-standing. We appreciate your comment, as we are always evaluating our process.
The disposition of the NIC for hydrogen sulfide will be released approximately February 1, 2005 in our Annual Reports for the Year 2004.
Your input is valuable and a very important part of our TLV/BEI Development Process. We appreciate your willingness to participate in our process. Thank you for your time and input.
Sincerely,
Jean Staubach
Science Coordinator
513-742-6163 x 105