Skip to content


Frequently Asked Questions
on Silica Dust Regulations and Workplace Safety

What is crystalline silica?

Crystalline silica is a naturally occurring mineral in various materials commonly found in industrial settings and construction sites. It can be found in sand, concrete, stone, and mortar materials. Additionally, crystalline silica is utilized in the production of various industrial products, including glass, pottery, ceramics, bricks, concrete, artificial stone, and some natural stone. It’s important to note that amorphous silica, like silica gel, differs from crystalline silica.

Are there any safety issues associated with finished products?

No, there are no safety issues with finished products themselves. Safety concerns related to the inhalation of silica dust can arise during the cutting, polishing, and fabrication of stone products. These issues are not related to the finished quartz or stone product, but to the manufacturing and installation processes.

Why is wet cutting considered the most effective method to reduce exposure to silica dust?

Utilizing appropriate controls including wet cutting effectively minimizes the risk of exposure to silica dust because the water suppresses the dust particles, preventing them from becoming airborne. This reduces the chances of employees inhaling hazardous silica dust.

How does exposure to crystalline silica impact workers’ health?

If proper safety methods, including wet cutting, are not followed, exposure to tiny, inhalable (“respirable”) crystalline silica particles over time can cause lung inflammation that leads to the development of scar tissue that makes breathing difficult. This continued exposure can lead to silicosis, which is an irreversible lung disease that can lead to disability and death.

What measures can be taken to control silica exposure and maintain it at or below the permissible exposure limit (PEL)?

Employers must prioritize the implementation of engineering controls and proper work practices to ensure that silica exposure remains at or below the designated permissible exposure limit (PEL). Here are some effective methods for achieving this:

  • Engineering Controls: These encompass various systems, such as using “wet cutting” equipment that wets down work operations or employing local exhaust ventilation systems (like vacuums) to effectively remove any remaining silica-containing dust from the air, thereby preventing it from entering workers’ lungs. Another effective method is enclosing the operation through “process isolation.”
  • Work Practices: Appropriate administrative controls can further reduce employee exposure to airborne crystalline silica. Examples include dampening dust before sweeping it and using wet cutting equipment consistently with the water flow rate recommended by the original equipment manufacturer.
  • Respirators: Engineering controls usually effectively reduce silica dust below permissible exposure levels, which can be proved with personal air monitoring data.  Respirators need to be used when it is impossible to maintain exposures at or below the permissible exposure limits through engineering controls and work practice adjustments.

By diligently implementing these control measures, employers can safeguard the health and well-being of their workers by minimizing exposure to hazardous crystalline silica particles.

What does exposure data indicate about the risk of illnesses related to silica exposure?

Exposure data shows that illnesses like silicosis can result from exposure to silica levels above specific permissible exposure limits. These illnesses are more likely to occur in industries where employees consistently engage in dry cutting of silica-containing products or otherwise fail to follow industry-defined best practices.

Why should enforcement efforts focus on wet cutting?

Focusing on wet cutting is recommended because decades of industrial hygiene research indicate that it helps to eliminate airborne silica dust hazards from workplaces. It is also cost effective, while other proposed additional requirements are more onerous, expensive, or ineffective at reducing hazards. Compliance with the Division’s proposed revisions may lead to significant expenses and potential loss of employees, while non-compliant employers may continue to dry cut and increase their market share, increasing the incidences of silicosis regardless of material.

What causes safety issues related to silica dust?

Safety issues related to silica dust are created when employers violate OSHA regulations during the cutting, polishing, and fabricating of stone products.  To prevent health hazards, fabricators and installers in the stone industry must adhere to all applicable air quality safety rules and regulations, including silica dust rules set by OSHA agencies. Dry cutting and dry grinding of stone products must be completely eliminated to protect workers’ health and safety.

Do fabricators and stone cutters in the US follow OSHA regulations?

Yes, the vast majority of fabricators and stone cutters in the US adhere to OSHA requirements and regulations when working with stone, including quartz, such that employees are not exposed to airborne silica dust above occupational exposure limits. These employers prioritize employee safety and health and follow proper procedures to prevent the release of silica dust. 

Can silicosis and dust-related hazards be prevented when working with stone products?

Yes, silicosis and other dust-related occupational hazards are preventable through established industrial engineering controls, hygiene, and strict adherence to OSHA requirements and regulations. It is essential to prioritize safety measures to protect workers.

Where are unsafe manufacturing and fabrication practices most concentrated?

Unsafe manufacturing and fabrication practices can be found throughout Los Angeles County. Negligent and/or uncooperative fabricators and stone cutters frequently violate state and federal OSHA laws. Strict enforcement and adherence to OSHA requirements and regulations are necessary in these fabrication shops to ensure safety.

What is being done to improve safety in the stone industry?

The National Stone Institute has been at the forefront of worker safety when handling stone products. They are working with Cal/OSHA to strengthen and enforce their requirements and regulations, focusing on eliminating all dry cutting, dry grinding, or dry polishing of stone products during fabrication. Collaboration between California regulators and industry stakeholders is key to ensuring the safety and health of stone workers in their workplaces.

Where can customers find more information about silica dust safety?

Customers with questions about silica dust safety can visit Cal/OSHA’s website for comprehensive information and resources here. Cal/OSHA provides valuable guidance on safety practices and regulations to protect workers in various industries, including those working with stone products.

Why are the regulations described as “task-based” rather than “hazard-based”?

The regulations are “task-based” because they require safety protocols for employers engaged in broadly defined tasks, some of which may pose minimal hazards when proper safety controls are in place. This approach may impose unnecessary requirements on businesses that perform these tasks infrequently, leading them to outsource such operations to avoid compliance.