Effective July 1, 2017, Cal/OSHA has implemented tighter restrictions on wood dust permissible exposure limits (PEL). The standard reduces the PEL by 50-80 percent compared to the previous regulation. While this means fewer particles are flying around in the air for workers to breathe in, it also means employers must implement stronger control measures to ensure compliance.

The updated regulation culminated at least eight years of discussion. The topic was first introduced in 2009, at a meeting of the Health Effects Advisory Committee (HEAC) within the Department of Industrial Relations (DIR). What followed was much discussion over the different breathing ailments and other illnesses linked to wood dust exposure and how a new standard can help reduce the risk of workers getting sick.

That same year, wood dust was added to California’s “Proposition 65” list of substances known by the state to cause cancer—a fact that was cited later by the DIR to further support the need for a new regulation.

How do I compare the new limits to the old ones?

For all soft and hard woods—with the exception of Western Red Cedar—the PEL is now 2 milligrams per cubic meter of air (mg/m3) over an eight-hour time period. That’s down from the previous standard of 5 mg/m3.

Western Red Cedar has a more strict exposure limit of 0.5 mg/m3 over the same eight-hour time period (down from 2.5 mg/m3). This tighter limit is due to an additional health factor: there’s a strong association between Western Red Cedar wood dust and occupational asthma.

How do I know if I’m in compliance?

To get an accurate reading on your wood dust levels, you can use a direct-reading instrument to measure the level of wood dust in the air. The Occupational Safety and Health Administration (OSHA) has information on how to use this specific device, which provides real-time or near real-time readings. OSHA has identified other tools that also can be used to measure exposures. The direct reading instruments and the other options are available online for loan, purchase, or rent.

What must I do to comply?

Reducing wood dust exposure can be accomplished with these steps: filtering dust out of the air, reducing dust being kicked up after it has already settled, and/or using a respirator.

Filtering. Individual dust capture systems for machines and tools effectively collect dust right at the source. A central exhaust ventilation system with collectors placed at woodworking points can also pull the wood dust from the air and out of your workers’ breathing space. Be sure to inspect and maintain your ventilation system, repair leaks, and regularly clean the filters, ducts, and collectors so they operate efficiently.

Reducing. Wood dust that has accumulated on tools, other surfaces, and the ground can release back into the air when you’re cleaning up. Dry sweeping or blowing the dust from equipment or floors should be avoided. A vacuum with a high-efficiency particulate air (HEPA) filter is safer, because it pulls the dust directly from the surface you are cleaning, preventing the particles from releasing back up into the air.

Respirators. These are required whenever dust levels exceed Cal/OSHA regulations or anytime an employee requests one. Respirators must also be approved by the National Institute for Occupational Safety and Health (NIOSH), and specialized to protect against wood dust. 

Complying with the new regulations can certainly be challenging. Respirators are required much earlier and much more frequently now that the PELs have been cut by 50-80 percent. And, the dust collection systems can be expensive. But, by taking the extra steps, you provide a safer workplace for your employees, help minimize their risk of contracting a serious illness, and help keep your workers’ comp costs in control.