Demonstrators outside the U.S. Chamber of Commerce in Washington in June. The group was delivering a petition urging the Chamber of Commerce to drop its opposition of the Occupational Safety and Health Administration’s (OSHA) proposed rule limiting worker exposure to silica dust. (Pablo Martinez Monsivais/AP)

Reaction to a controversial new Obama administration regulation designed to protect workers from toxic dust particles demonstrates the divide that often develops between government and business, and a focus on health or a focus on cost.

The Occupational Safety and Health Administration (OSHA) says the rule limiting exposure to the dust, known as respirable crystalline silica, annually will save more than 600 lives and prevent more than 900 new cases of incurable silicosis, a lung disease. Exposure also can lead to lung cancer, pulmonary disease and kidney ailments.  OSHA expects the regulation, announced Thursday, eventually will result in net benefits worth $7.7 billion every year.

Silica is found in the construction, maritime and numerous other industries. OSHA estimates about 2 million construction workers in more than 600,000 workplaces are exposed to it. The exposure level for more than 40 percent of those workers is greater than that provided by the new rule, according to the Labor Department. In maritime and general industry, including dental labs, foundries and railroads, more than 100,000 workers face exposure levels higher than permissible under the new rule.

Among other things, the regulation limits exposure to crystalline silica to an average of 50 micrograms per cubic meter of air over an eight-hour shift and mandates ventilation practices.

“This rule will save lives,” said Labor Secretary Thomas E. Perez. “It will enable workers to earn a living without sacrificing their health. It builds upon decades of research and a lengthy stakeholder engagement process – including the consideration of thousands of public comments – to finally give workers the kind of protection they deserve.”