A coalition of construction industry associations has asked the Occupational Safety and Health Administration (OSHA) to withdraw its proposal to tighten crystalline silica exposure limits for construction workers.

But organized labor, including the AFL-CIO’s Building and Construction Trades Dept., says that the proposed rule is necessary to protect workers from developing silicosis, cancer and other silica-related illnesses.

The proposed rule, published in the Sept. 12, 2013, Federal Register, would set a new permissible exposure limit standard of 50 micrograms per cubic meter (µg/m3), which is much tougher than the existing standard of 250 µg/m3.

The proposal offers three discrete approaches to reduce exposure to silica. The first would allow contractors to follow the recommendations for certain construction tasks listed in a table (Table 1) in the proposed rule.

The second would allow firms to use “objective data” to determine which protections are necessary on a given site.

The third would follow the traditional path of other major workplace-health standards, requiring air sampling and monitoring. Then, if silica levels exceed the permissible limit, a company would have to develop a plan to reduce them.

In comments submitted to OSHA on Feb. 14, a coalition of 25 construction industry groups—including the Associated General Contractors of America, Associated Builders and Contractors and American Road & Transportation Builders Association (ARTBA)—said the proposed rule is “significantly flawed” and should be withdrawn.

The groups also say that they are not necessarily opposed to a standard, but add that OSHA in its proposal has failed to justify the need for a more stringent standard by relying on studies that do not reflect current industry practices.

Bradley Sant, ARTBA senior vice president of safety and education, told ENR, “We’re very much in favor of a standard, but we want one that is workable and makes sense.”

Sant says that the studies OSHA cites in its proposal draw on data from before OSHA came into existence in the 1970s. “A lot of the evidence OSHA is relying on is based upon exposures before the U.S. [construction] standard was in place,” he says. Moreover, the proposed rule underestimates the costs for businesses to adhere to the new benchmark, Sant says. “We think the costs of complying with the standard would be astronomical.”