OSHA PLANS TO CUT BUTADIENE EXPOSURE LIMIT

The U.S. Occupational Safety and Health Administration has proposed a sharply lower exposure limit for butadiene. The agency's permissible exposure limit would drop from 1,000 ppm in air to 2 ppm as an 8 hr time weighted average. OSHA also proposed a short term exposure limit of 10 ppm for 15 min. U.S. companies produced 3 billion lb of butadiene in 1989. It has been linked to various types of cancer in animals. The proposal would cover nearly 100 plants, more than half of which produce

Aug. 27, 1990

2 min read

The U.S. Occupational Safety and Health Administration has proposed a sharply lower exposure limit for butadiene.

The agency's permissible exposure limit would drop from 1,000 ppm in air to 2 ppm as an 8 hr time weighted average.

OSHA also proposed a short term exposure limit of 10 ppm for 15 min.

U.S. companies produced 3 billion lb of butadiene in 1989. It has been linked to various types of cancer in animals.

The proposal would cover nearly 100 plants, more than half of which produce 1,3-butadiene polymer, one third produce crude 1,3-butadiene, and the balance refine the product.

OSHA estimates compliance costs at $3.2 million/year.

WHAT'S REQUIRED

The OSHA program proposes a number of requirements including provisions for exposure control, work practices and personal protective equipment, measurement of employee exposures, training, medical surveillance, hazard communication, regulated areas, emergency procedures, and record keeping.

The agency is seeking comments on the proposed standard before Oct. 19. It also plans hearings Dec. 11 in Washington and Jan. 8, 1991, in New Orleans.

OSHA said exposures to butadiene occur when workers load or unload the chemical, take samples of products, or handle it in laboratories. Workers also may be exposed during maintenance operations, when venting waste gases, or when leaks or spills occur.

It said about 5,700 workers/year are exposed to the gas, ranked as the 35th most important chemical in the U.S. largely because it is a building block for synthesizing other products.

OSHA's risk assessment shows an excess cancer risk of 147 deaths per 1,000 workers during a 45 year working lifetime at the current exposure rate of 1,000 ppm.

"This proposal to reduce exposures to 2 ppm will achieve an approximately 97% reduction in risk or 142 lives saved ... and clearly is substantial," the agency said.