The OSHA Silica Standard and How Employers Comply

OSHA's silica standard limits how much respirable crystalline silica dust a worker may breathe to 50 micrograms per cubic meter of air (50 µg/m³), averaged over an 8-hour shift.

There are two versions of the rule. 29 CFR 1926.1153 covers construction. 29 CFR 1910.1053 covers general industry and maritime. The hazard both cover is respirable crystalline silica, which is dust from quartz, cristobalite and tridymite. It is produced when workers cut, grind, drill, crush or blast stone, concrete, brick and similar materials.

According to OSHA, about 2.3 million people in the United States are exposed to silica at work. The particles are at least 100 times smaller than ordinary sand. They reach deep into the lungs. Exposure causes silicosis, which is incurable. It is also linked to lung cancer, chronic obstructive pulmonary disease (COPD) and kidney disease.

The federal exposure limits did not change in 2026. They were set by the rule published on March 25, 2016. The 2026 developments are in enforcement, guidance and state law. They are described below.

Who it applies to. The construction standard applies to any worker whose exposure could reasonably reach or exceed the action level. It does not apply only where exposure will stay below 25 µg/m³ under all reasonably foreseeable conditions.

The two limits.

• Permissible exposure limit (PEL): 50 µg/m³ as an 8-hour time-weighted average. No worker may be exposed above this.
• Action level (AL): 25 µg/m³ as an 8-hour time-weighted average. This is the point at which the standard's obligations begin.

Two ways to comply. The employer chooses one path for each task.

• Table 1. The standard lists common tasks, such as handheld and stationary power saws, grinders, chipping and drilling tools, abrasive blasting, crushing and screening, and demolition. For each task it specifies the engineering controls, work practices and respiratory protection. If the employer follows Table 1 fully for a task, no air monitoring is required for that task.
• Exposure assessment. If a task is not on Table 1, or the employer does not follow Table 1 fully, the employer must assess exposure. This is done through performance or scheduled monitoring. The employer then selects controls that keep exposure at or below the PEL. Some employers rely on objective data instead of air monitoring where the data supports it.

Obligations on every covered employer.

• Written exposure control plan. The plan lists the tasks that generate silica, the controls for each task, housekeeping methods and procedures for restricting access. It must be reviewed and updated at least once a year. The required contents of the written exposure control plan are set out in 1926.1153(g).
• Competent person. The employer must designate a person who can identify silica hazards and has authority to correct them. This person inspects the jobsite regularly and makes sure the plan is carried out.
• Housekeeping. Dry sweeping, dry brushing and cleaning with compressed air are prohibited unless no feasible alternative exists. A HEPA filter under the standard must remove at least 99.97% of particles 0.3 micrometers in diameter.
• Other contractors. On multi-employer sites, the employer must account for silica created by other contractors' work.
• Training. Workers must be trained on the health hazards, the tasks that expose them, the controls in use and the contents of the standard.

Medical surveillance. If a worker is required to wear a respirator for 30 or more days a year, the employer must offer medical exams.

• The initial exam is due within 30 days of assignment. It is not required if the worker had an equivalent exam in the previous 3 years.
• The exam includes a chest X-ray, a pulmonary function test and a physical exam. The initial exam also includes a test for latent tuberculosis.
• Follow-up exams are due at least every 3 years. They are due sooner if the physician recommends it.
• The employer pays for all exams.

Records. The employer must keep records of air monitoring, objective data and medical surveillance. Medical records are kept under 29 CFR 1910.1020, which generally means 30 years.

A federal citation in brick manufacturing. OSHA inspected Plant 3 of General Shale Brick Inc., doing business as Watsontown Brick Company, in Watsontown, Pennsylvania, on February 12, 2026. The inspection came under the Site-Specific Targeting plan and the silica National Emphasis Program. OSHA announced the citations on August 26, 2026, under the general industry standard, 29 CFR 1910.1053. OSHA alleged that the company:

• knew workers were exposed above the PEL and did not install engineering controls or require respirators
• did not conduct annual respirator fit testing
• did not establish regulated areas
• did not monitor exposure in all relevant job classifications
• did not provide medical exams to workers exposed more than 30 days a year

The proposed penalty was $496,528. It covered 3 willful, 4 serious, 1 repeat and 1 other-than-serious violation. The repeat violation arose from an earlier fit-testing citation at the company's Augusta, Georgia plant.

State enforcement in California. The California Department of Industrial Relations reports that Cal/OSHA's Silica Special Emphasis Program issued more than 900 citations, with about $1.9 million in proposed penalties. The California Occupational Safety and Health Standards Board voted unanimously to begin expedited rulemaking to prohibit fabrication and installation of artificial stone containing more than 1% crystalline silica. The ban is not yet in effect. Emergency findings and advisory committee review must come first.

Countertop work. In 2026 OSHA issued a Hazard Alert on worker exposure to silica during countertop manufacturing, finishing and installation. It is available in English and Spanish.

The action level is not the exposure limit. Exposure between 25 and 50 µg/m³ is legal, but it brings a worker under the standard's requirements.

The construction standard and the general industry standard are separate rules. A brick plant, like the one in the case above, is cited under 1910.1053, not 1926.1153.

The California artificial stone ban is a state proposal. It does not change the federal standard.