Table of Contents
- What Is Crystalline Silica?
- What Causes Respirable Silica?
- What Are the Health Effects of Respirable Crystalline Silica?
- What Are the OSHA Standards for Respirable Crystalline Silica?
- How to Protect Your Crew From Crystalline Silica Dust Hazards
- Browse Our OSHA Silica Safety Training Courses
Workers across various industries face exposure to respirable crystalline silica. Complying with the Occupational Safety and Health Administration (OSHA) standards and best practices helps you protect your employees and stay compliant. In this OSHA silica compliance guide, we’ll assess what crystalline silica is, sources of respirable silica, OSHA standards and the health challenges associated with exposure.
What Is Crystalline Silica?
Silicon dioxide — also known as crystalline silica — is a common mineral in the earth’s crust. Crystalline silica is chemically inert, hard and has a high melting point. This valuable industrial material is available in various forms, including the following:
- Quartz: The most common form of crystalline silica is quartz, an abundant mineral on the earth’s surface. It can appear in igneous, sedimentary and metamorphic rocks, making it present in most mining operations.
- Cristobalite: Cristobalite is scarce compared to quartz. You can find it in some meteorites and volcanic rocks. It also forms when quartz reaches temperatures exceeding 842 degrees Fahrenheit. Cristobalite exposure is most common in occupational settings.
- Tridymite: Like cristobalite, you can find tridymite in meteorites and volcanic rocks. However, tridymite is less stable during conventional quartz and refractory materials heating processes, making them less likely to occur in occupational settings.
What Causes Respirable Silica?
Silica dust, or respirable crystalline silica, typically forms when cutting, grinding, sawing, drilling and crushing rocks, stone, concrete, block, brick and mortar. These activities send tiny dust particles into the air.
According to OSHA, about 2.3 million people in the U.S. face silica exposure at work. When these workers inhale silica dust, it exposes them to several silica-related diseases.
What Are the Health Effects of Respirable Crystalline Silica?
Inhaling minute crystalline silica particles can cause multiple diseases, including silicosis, lung cancer, kidney disease and chronic obstructive pulmonary diseases (COPDs). Although some of these conditions are incurable, they are preventable. Let’s consider each in detail:
Silicosis occurs when silica dust enters the lungs. The abrasion causes scar tissue to form, making it challenging for the lung to take in oxygen. The damage also affects the immune system, increasing the risk of respiratory conditions and lung infections. This condition can be disabling or fatal in severe cases. Scientists are yet to find a cure for silicosis.
Silicosis typically occurs after 15 to 20 years of occupational exposure to silica dust. Because early symptoms are less likely to show, workers may require chest X-rays to detect lung damage. Symptoms are more extreme during the later stages of development. They may start to experience fatigue, chest pain, shortness of breath or even respiratory failure.
2. Lung Cancer
Exposure to respirable crystalline silica can lead to an increased risk of lung cancer. Lung cancer occurs due to the uncontrolled growth of abnormal cells into tumors, interfering with the lung’s function. The abnormal cells may also travel and cause damage to other parts of the body.
3. Kidney Disease
Workers who face exposure to respirable crystalline silica have a higher risk of developing kidney diseases, which may lead to kidney failure. It’s vital to ensure that workers facing high exposure — like those who work with abrasive blasters — are well-trained and equipped with protective gear.
4. Chronic Obstructive Pulmonary Diseases
COPDs, including chronic bronchitis and emphysema, are lung diseases that may arise due to exposure to respirable crystalline silica. Symptoms of COPDs include coughing, production of sputum or phlegm and shortness of breath. Since these conditions may be irreversible and worsen over time, ensuring optimal safety is crucial.
What Are the OSHA Standards for Respirable Crystalline Silica?
The OSHA respirable crystalline silica standards protect industry workers against harmful exposure to respirable crystalline silica. Those standards include the following:
1. Permissible Exposure Limits
OSHA’s permissible exposure limit for respirable crystalline silica is 50 micrograms per cubic meter of air. Exposure to this maximum concentration can occur throughout an eight-hour time-weighted average (TWA). They also define 25 micrograms per cubic meter of air, averaged over an eight-hour day, as the respiratory silica action level.
2. Employer Obligations
The standards require general industry and maritime employers to monitor and identify silica concentrations. They must also take reasonable measures to eliminate or mitigate the dangers they may cause to workers. Where exposure exceeds the permissible exposure limit, employers must provide respiratory protection.
3. Crystalline Silica Exposure Control Plan
Employers must create a written crystalline silica exposure control plan describing how they will minimize exposure. This written exposure control plan helps identify the tasks that expose workers to respirable crystalline silica and establishes the procedures for protecting them. For example, the plan may include controlling exposure through ventilation, vacuums, isolating processes or using water to control airborne dust.
4. Medical Evaluations and Surveillance
Some jobs and industries may require workers to frequently face respiratory silica exposure above the action level. If exposure exceeds the action level for 30 or more days a year, workers must receive a chest x-ray and other tests every three years.
Routine medical surveillance helps early detection of silica-related diseases and provides preventive measures for maximum safety. It also determines workers’ fitness to wear a respiratory mask.
One of the most integral aspects of protection against silica-related hazards is providing workers with quality training programs. Training makes it easier for employers to understand the dangers and control procedures. It also keeps stakeholders up to date with changes to the OSHA standards and helps you stay compliant.
How to Protect Your Crew From Crystalline Silica Dust Hazards
Complying with the OSHA standards helps protect your crew from crystalline silica exposure. Some best practices include:
- Using water to control dust levels.
- Ensuring proper ventilation and using vacuums to collect dust.
- Limiting employee access to areas above the permissible exposure limit.
- Providing respiratory protection where necessary.
- Restricting housekeeping practices.
- Utilizing recommended water flow rates for tools with water controls.
- Ensuring that all workers comply with the established procedures.
- Employing regular and comprehensive training programs.
Browse Our OSHA Silica Safety Training Courses
Silica exposure is common in general industry, construction and maritime operations. The health complications associated with exposure make it crucial to comply with OSHA standards and best practices. Employers must observe their legal duties to provide safe working conditions, tools and the education and training necessary to prevent or mitigate silica exposure.
Hazmat School offers OSHA safety courses for businesses involved in construction, concrete production, railroad transportation and other related industries. We aim to help you stay compliant while enjoying the best training at competitive prices. Browse our silica safety courses today or contact us for more information!