Cal/OSHA Clarifies Requirements on Lead Exposure during Abrasive Blasting
New notes added to the website of the California Division of Occupational Safety and Health (Cal/OSHA) clarify the state agency’s requirements for protecting construction workers involved with dry abrasive blasting from lead exposure. Revisions to California’s lead standards for general industry and construction were approved last year, and the updated regulations went into effect on Jan. 1, 2025. Both amended standards lowered the state’s permissible exposure limit for lead from 50 µg/mg3 to 10 µg/mg3 as an eight-hour time-weighted average. Cal/OSHA’s clarifications have to do with the PEL, limits on the time construction workers can spend per day conducting abrasive blasting, and respiratory protection for these workers.
California’s construction standard for lead provides an exception for employees conducting abrasive blasting, allowing a PEL of 25 µg/m3 as an eight-hour TWA during such tasks until Jan. 1, 2030. The standard also limits the number of hours a worker can spend conducting dry abrasive blasting per day until their employer performs an exposure assessment to determine the worker’s actual exposure. Until Jan. 1, 2030, a worker whose employer has not yet conducted the required exposure assessment can spend up to five hours per day abrasive blasting, and after Jan. 1, 2030, that limit becomes two hours per day. According to Cal/OSHA, there is no limit on the amount of time per day a worker can conduct abrasive blasting once the required exposure assessment is complete, “but the employer must ensure employee exposures are below the [PEL] taking into consideration the protection provided by respirators used by employees.”
Cal/OSHA’s notes on abrasive blasting and lead include a copy of a table that describes the protection provided by different types of respirators. Taking into consideration the state’s exception for the construction industry PEL, the agency explains that air concentrations of lead up to 25,000 µg/mg3 are permitted for abrasive blasting until Jan. 1, 2030. Starting on that date, air concentrations of lead will be limited to 10,000 µg/mg3. These maximum air concentrations are allowed for “employees correctly using a respirator with a protection factor of 1,000 at all times,” the agency states, as such respirators would reduce air concentrations of lead inside workers’ respirators to 25 µg/m3 and 10 µg/m3, meeting the respective PELs for before and after Jan. 1, 2030.
Abrasive blasting is among jobs that California’s regulation for lead in construction describes as “level 3 trigger tasks,” which put workers at the highest risk of lead exposure. Until an employer performs the required exposure assessment, they must assume that workers involved in level 3 trigger tasks are exposed to lead at more than 50 times the revised PEL of 10 µg/mg3, or more than 500 μg/m3.
Information about Cal/OSHA’s clarifications for its standard on lead in construction can be found in an agency news release and on its webpage for lead exposure prevention in the construction industry. Additional guidance and resources related to California’s lead standards for both construction and general industry are also available from Cal/OSHA.
Related: An article published in the December 2023 issue of The Synergist discussed efforts at the federal and state levels to update lead standards.
