The order by the U.S. Appeals Court for the 3rd Circuit gives the agency until January 2006 to issue a final rule with new exposure limits for the chemical, which has been shown to cause lung cancer if inhaled at certain levels. A proposed rule must be issued by October 4.

The court order was in response to a lawsuit filed last year by Public Citizen and the Paper, Allied-Industrial, Chemical and Energy Workers International Union. The lawsuit claimed that OSHA was aware that its current exposure limit posed a cancer risk to workers, but has continually delayed any action. The groups have urged OSHA to lower the limit for more than a decade.