About the Standard

OSHA sets exposure limits for dust, chemicals and other materials that employees may be exposed to at work or on a jobsite. These exposure limits cover dust from all types of materials, including: stone, brick, concrete, drywall, wood, and wood composites.

OSHA requires employers to take specific actions to protect workers on construction sites based on the amount of silica dust they are exposed to. The updated OSHA standard reduces the permissible exposure limit (PEL) for silica dust by about 80% – from 250 μg/m³ to 50 μg/m³ – over an 8-hour period.


How It’s Measured

Silica exposure is determined one of two ways:

  • By referencing objective data, which means studies or reports by recognized experts who have evaluated dust exposures for certain tasks*
  • By directly monitoring actual employee exposure
Actual exposure is measured using an air sampling device that is placed in the work area or worn by an employee. An industrial hygienist (IH)** will generally oversee the sample collection. The samples are collected and sent to a qualified lab for analysis and the IH will review the results and make recommendations.


Who Is Affected?

This new standard affects all activities that generate silica dust on a jobsite. Trades involving brick, stone, concrete and other materials that are difficult to replace must also comply with the standard, as this is a change around process, not specific products.

Cutting fiber cement does not require a dust mask or respirator when using the tools specified in Table 1.

What is Table 1?

* The National Institute for Occupational Safety and Health (NIOSH) published several reports related to controlling silica dust on jobsites, including concrete grinding, tuck-pointing and fiber cement. See Link
** Industrial Hygienists are degreed scientists or engineers trained to evaluate workplace health and safety issues. While there is no licensing program, the American Board of Industrial Hygiene administers a certification program; Certified Industrial Hygienists (CIH) must have be degreed, have least four years of experience and pass a 1-day exam. See Link

James Hardie is here to help

When using James Hardie products, working with the new OSHA silica dust standard is straightforward and can be as easy as making a plan, using the right tools and training your employees. We’re ready to help you with all three.


Don’t hesitate to contact James Hardie. Complete this form or call James Hardie Technical Services at 800-942-7343.

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