Dust to Disease: Silicosis and How to Prevent It

More than 2 million workers are exposed to crystalline silica every year in the United States. When inhaled, very small (respirable) particles of crystalline silica dust travel deep into the lungs and become trapped there, causing chronic inflammation and scar tissue. This condition is called silicosis, which reduces lung function and makes it hard for the body to get oxygen. Symptoms of silicosis include cough, fatigue, chest pain, and shortness of breath.

There is no cure for silicosis. The disease is debilitating—causing weakness, pain, and limiting life activities; progressive—it continues to cause lung damage and gets worse over time; and deadly. Workers exposed to respirable crystalline silica are at increased risk of lung cancer, chronic obstructive pulmonary disease (COPD), kidney disease, tuberculosis infection, and autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, and scleroderma.

The three types of silicosis

Development of silicosis depends on many factors such as the amount of crystalline silica in the dust inhaled, the size of the particles, and the length of exposure.

Chronic. Usually occurs after 10 or more years of exposure to respirable crystalline silica at moderate to low concentrations. Symptoms include shortness of breath, wheezing, and decreased lung function. Chronic has historically been the most common type of silicosis.

Accelerated. Results from exposure to high concentrations of respirable crystalline silica over 1-10 years. Symptoms are like chronic but occur more rapidly.

Acute. Occurs after exposure to extremely high concentrations of respirable crystalline silica over a short time, such as a few weeks to months. Symptoms include cough, fatigue, chest pain, and low blood oxygen levels. Acute silicosis progresses rapidly and can be fatal within months.

All types of silicosis are incurable and potentially fatal.

What is crystalline silica?

Crystalline silica (also referred to as silica) is a plentiful, naturally occurring mineral, commonly found as quartz. It is hard, chemically inert, and has a high melting point, making it useful for many applications.

Many common construction materials contain silica. These include stone, brick, concrete, sand, ceramic roof tile, joint compound, and natural and artificial stone countertops. The amount in countertops varies greatly, with engineered stone containing more than 90 percent crystalline silica.

How can you be exposed to silica?

Exposure can occur when working with materials that contain silica. When these materials are disturbed such as during cutting, grinding, crushing, drilling, and polishing, the dust becomes airborne and can be inhaled. Those working in the stone countertop fabrication and construction industries are most at risk. Other industries where workers are at risk of silica exposure include:

Stone cutting
Foundry operations
Abrasive blasting
Oil and gas extraction
Glass manufacturing
Stone and cement crushing
Demolition
Mining, quarry, and milling operations
Road construction

IMPORTANT

Cal/OSHA has strict industry-dependent silica regulations. For construction, Table 1 has task-based requirements. For all others, the general industry regulation applies. Stone countertop workers have even stricter rules. Look under additional resources for compliance info for your industry.

How can you prevent silicosis?

Workers can be protected from silicosis by controlling exposure to silica-containing dust. Eliminate or reduce dust exposure using the hierarchy of controls:

Elimination/substitution

Choose no or low silica containing materials if possible.
Check with the manufacturer or review the product’s safety data sheet.

Engineering controls

Use tools with integrated water or ventilation systems to control dust at the source.
Isolate employees from dust using ventilated enclosures.
Maintain equipment and keep cutting blades sharp.

Work practices and procedures

Train employees on health effects of silica and how to reduce exposure.
Practice good housekeeping using wet methods or a HEPA-filtered vacuum.
Do not allow the use of compressed air for cleaning.
Limit access to work areas during dust generating tasks.
Provide medical surveillance for silica related diseases.

Personal protective equipment (PPE)

Determine proper type of respirator for the task.
Ensure respirators are properly fitted and NIOSH-approved with a particulate filter (HEPA or N/R/P100).
Use coveralls to keep dust off street clothes.
Carefully remove PPE so dust is not inhaled—remove respirator last!

Employee training

Cover silica health hazards and how employees should protect themselves.
Follow Cal/OSHA construction and general industry training requirements.

Silicosis was first identified in stone cutters over 300 years ago. Silicosis is 100% preventable. Protect your employees by controlling their exposure to silica, train them on the hazards of exposure, and provide the appropriate PPE. There’s no better time than the present.

(Rev. 02/2025)