Appeals Court Sides With OSHA In Case Challenging Threshold Limit Values

ON May 11, a unanimous panel of three judges from the U.S. Court of Appeals for the District of Columbia Circuit sided with OSHA and the U.S. Labor Department (DOL) in a key case involving Threshold Limit Values (TLVs), which OSHA recognizes but some industry groups attack because they are privately developed.

OSHA's recognition of updated TLVs does not involve rulemaking and thus does not give stakeholders a chance to oppose them, the National Association of Manufacturers (NAM) argued in National Association of Manufacturers vs. OSHA and Elaine Chao, Secretary of the United States Department of Labor, No. 06-1122.

In an opinion written by Judge David S. Tatel, the judges agreed with DOL and dismissed NAM's lawsuit as untimely -- a clear victory for the OSHA/DOL argument that OSHA's recognition of new TLVs issued by the American Conference of Governmental Industrial Hygienists (ACGIH) on Jan. 31, 2006, did not reopen or revise the Hazard Communication Standard (HCS) itself, which would require formal rulemaking.

This case primarily concerns how particular chemicals are classified as hazardous. Rather than attempting to identify every hazardous chemical, the HCS "places primary responsibility for determining which products are hazardous on the chemical manufacturer or importer." Thus, the HCS defines a chemical as hazardous if "there is statistically significant evidence based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur in exposed employees," and requires that companies "evaluate chemicals produced in their workplaces or imported by them to determine if they are hazardous."

Under this "one-study" rule, a company that manufactures a particular chemical is free to decide that a scientific study about that chemical is either unreliable or inapplicable, in which case it need not treat the chemical as hazardous. Companies choosing this option risk enforcement proceedings if OSHA disagrees with their assessment. The HCS, however, takes two categories of hazard determinations out of company hands. First, it deems hazardous any substance on OSHA's list of Toxic and Hazardous Substances. Second, and central to this case, the HCS provides that chemicals must be treated as hazardous if included in the "latest edition" of the TLV list published by ACGIH.

Under the OSH Act, parties adversely affected by a safety or health standard have 60 days after promulgation to petition for review. OSHA argued the HCS was enacted in 1983, and NAM's petition for review was filed 20 years too late. The U.S. Chamber of Commerce and other industry groups intervened in the case on the side of NAM, which was challenging five new substances on the 2006 TLV list, nine lowered TLVs, and other changes it considered substantial affecting chemicals made or used by NAM members.

Tatel wrote that NAM failed to argue in its opening brief that it lacked a meaningful opportunity to challenge the standard in 1983 or 1987, so the judges did not decide whether they should grant in this case an exception to the 60-day requirement -- an exception this court recognized in a 1985 decision involving EPA.

"NAM asks us to understand the HCS as defining the conditions required of its members not in terms of a general obligation to comply with the current TLV list, but more specifically in terms of the particular chemicals that industry must treat as hazardous. Yet treating the HCS as prescribing the particular chemicals for which hazard communications are required, as opposed to the system for recognizing such chemicals, would directly contradict the regulatory scheme OSHA established in 1983," Tatel wrote. "With minor exceptions not relevant here, the HCS identifies no specific chemicals as hazardous, instead leaving their evaluation to ACGIH and, in the case of the one-study rule, to regulated entities themselves."

Quentin Riegel, NAM's vice president, litigation, said he had watched the oral arguments March 28, 2007, and thought they went well. "We were quite surprised and concerned by the decision," he said on May 11. "It sets a dangerous precedent of allowing OSHA to regulate by proxy." The decision allows OSHA to regulate through outside parties that lack OSHA's notice and comment procedures, Riegel said. "There really are new obligations imposed on employers every year" by OSHA's HazCom standard, he added. Riegel said no decision had been made at this point to file a rehearing request or appeal to the U.S. Supreme Court.

The D.C. Circuit's opinions can be accessed at

NAM's petition for review can be accessed in PDF format at

A brief filed by the U.S. Chamber of Commerce can be found at (scroll down to view the brief in PDF format).

More information on the Hazardous Communication Standard can be found at

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