OSHA submitted the proposed rule on respirable crystalline silica, which has been in the works for 14 years, to OMB's Office of Information and Regulatory Affairs (OIRA) in February 2011. While an executive order compels OMB complete its review of proposed rules within 90 days, OMB has held the rule for nearly a year with no indication of when it will be complete. This "extraordinary delay" is harming American workers, the stakeholders argued.

The letter also stated that OMB staff held multiple private meetings concerning the rule with individuals who "represent companies with a direct financial interest in the matter."

An estimated 1.7 million workers in the United States are exposed to respirable crystalline silica, a product of industrial processes like stonecutting, road building and sand blasting that can cause lung cancer, silicosis and other respiratory illnesses. The Centers for Disease Control and Prevention report that about 200 workers die each year from silicosis, and studies estimate there are as many as 7,300 new cases of silicosis annually among U.S. workers.

"When a person with silicosis starts to have trouble breathing, it is too late for effective treatment because the silica dust has caused permanent scarring of the lungs," said Dr. Robert Harrison, Clinical Professor of Medicine at University of California San Francisco and an occupational disease expert who signed the letter. "When I see a patient with silicosis, it's a stark reminder that our worker safety regulations are inadequate. Silicosis is 100 percent preventable."

This group of concerned safety and stakeholders isn't the first to complain about the OMB delay. In November 2011, the American Industrial Hygiene Association (AIHA) President Elizabeth L. Pullen, CIH, urged OMB to "to release the rule, defer to OSHA's scientific judgment as much as possible, and publicly reassure stakeholders that they will have plenty of opportunity for comment and input into the development of a final rule on silica."

Signers of the Jan. 25 letter include public health and occupational safety advocates from 39 states and the District of Columbia along with several advocacy groups, including the National Council for Occupational Safety and Health, the Union of Concerned Scientists and Interfaith Worker Justice. The letter may be downloaded a PDF.

"The White House's job is to coordinate the development of rules that protect the public, not to stand in their way," said Francesca Grifo, director of the Union of Concerned Scientists' Scientific Integrity Program. "The OMB is hundreds of days behind schedule, and every day these rules are delayed, more workers are at risk."