ACGIH(r)'s (Cincinnati, OH) board of directors recently announced that it has completed its Statement of Position Regarding the Threshold Limit Values (TLVs[r]) and Biological Exposure Indices (BEIs[r]). The Statement of Position, which was adopted by the board earlier this year, is being published to assist ACGIH members, government regulators, and industry groups in understanding the basis and limitations of the TLVs and BEIs when used in a regulatory context. The guidelines, which are developed to assist in the recognition and control of potential workplace health hazards, do not consider economic or technical feasibility, and should not be adopted by government or industry as a matter of course. Rather, they are designed to aid occupational health professionals in evaluating specific workplace situations and conditions.