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Frequently Asked Questions

What is silica?

When is silica a hazard for construction workers?

What construction materials contain silica?

How much silica dust is too much?

What illnesses can result from breathing in dust that contains silica?

What is silicosis?

I don’t know anyone with silicosis so why should I be worried?

How many people are diagnosed with silicosis each year?

How should I avoid bringing dust home on my clothes?

What should employers do to protect their employees?

How do I prevent exposures and control the dust?

What can I do to protect myself?

Where can I find out about silica related rules and regulations?

Where can I find help in my area on silica?

If my task isn't on Table 1, what do I have to do to comply with the standard?

If my task is listed on Table 1 do I have to follow Table 1?

When do respirators need to be used and what type should be used?

How do I clean dust on surfaces?

What is a competent person under the standard and what are they responsible for?

Do I need to provide all of my employees with medical surveillance?


Preguntas frecuentes (Frequently Asked Questions - Spanish)



  1. What is silica?
    Silica is one of the most common naturally occurring elements on the planet. Silica, the mineral compound silicon dioxide (SiO2), is found in two forms -- crystalline or noncrystalline (also referred to as amorphous). Sand and quartz are common examples of crystalline silica.

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  2. When is silica a hazard for construction workers?
    Materials that contain crystalline silica are not hazardous unless they are disturbed, generating small-sized particles that can get in your lungs (“respirable crystalline silica”).  For example, blasting, cutting, chipping, drilling and grinding materials that contain silica can result in silica dust that is hazardous for construction workers and others to breathe. For a list of construction materials that contain silica go to the “Know the Hazard” section of this website.

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  3. What construction materials contain silica?
    Many common construction materials contain silica including, for example, asphalt, brick, cement, concrete, drywall, grout, mortar, stone, sand, and tile.  A more complete list of building materials that contain silica, as well as information on how to find out if the material you’re working with contains silica, can be found in Step 1 of the Create-A-Plan section of the website.

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  4. How much silica dust is too much?
    It only takes a very small amount of the very fine respirable silica dust to create a health hazard.  Recognizing that very small, respirable silica particles are hazardous, OSHA regulation 29 CFR 1926.55(a) requires construction employers to keep worker exposures at or below a Permissible Exposure Level (PEL) of 50 µg/m3.  The American Conference of Governmental Industrial Hygienists has a lower non-regulatory Threshold Limit Value of 25 µg/m3.  More information about the hazard and links to examples of exposures with and without controls compared to the OSHA PEL, can be found at "Know the Hazard? Why is Silica Hazardous?".

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  5. What illnesses can result from breathing in dust that contains silica?
    Inhaling crystalline silica can lead to serious, sometimes fatal illnesses including silicosis, lung cancer, tuberculosis (in those with silicosis), and chronic obstructive pulmonary disease (COPD). In addition, silica exposure has been linked to other illnesses including renal disease and other cancers. In 1996, the World Health Organization – International Agency on Cancer Research (IARC) identified crystalline silica as a “known human carcinogen” (they reaffirmed this position in 2009).  The American Thoracic Society and the American College of Occupational and Environmental Medicine have also recognized the adverse health effects of exposure to crystalline silica, including lung cancer.

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  6. What is silicosis?
    Silicosis is a disabling, irreversible, and sometimes fatal lung disease. When a worker inhales crystalline silica, the lungs react by developing hard nodules and scarring around the trapped silica particles. If the nodules become too large, breathing becomes difficult and death can result. The risk of silicosis is high for workers in several industries, including the construction industry, according to the Center for Disease Control (CDC), the National Institute for Occupational Safety and Health (NIOSH), and the Occupational Safety and Health Administration (OSHA).

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  7. I don’t know anyone with silicosis so why should I be worried?
    Unlike a work-related injury where the effects are seen immediately, silicosis and other silica-related illnesses may not show up for many years after exposure.  The most common early symptoms are a chronic dry cough and shortness of breath with physical activity. There are three types of silicosis:
    • Chronic silicosis, which usually occurs after 10 or more years of exposure to crystalline silica at relatively low concentrations;
    • Accelerated silicosis, which results from exposure to high concentrations of crystalline silica and develops 5 to 10 years after the initial exposure; and
    • Acute silicosis, which occurs where exposure concentrations are the highest and can cause symptoms to develop within a few weeks to 4 or 5 years after the initial exposure.
    Silicosis is a progressive disease – meaning it continues to get worse, even when exposure to respirable silica has stopped.

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  8. How many people are diagnosed with silicosis each year?
    Millions of workers are exposed to dust containing silica.  A recent study, Estimating the Total Number of Newly-Recognized Silicosis Cases in the U.S., determined that between 3,600 to 7,300 new cases of silicosis occur annually in the United States.  However, only two of the 50 states, New Jersey and Michigan, have surveillance programs to track cases of silicosis.  As a result, many cases of silicosis are not reported and many more are not properly diagnosed. One study, Previously Undetected Silicosis in New Jersey Decedents, which reviewed the chest x-rays of individuals exposed to silica dust during their life-time, found evidence of silicosis that had not been diagnosed.

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  9. How should I avoid bringing dust home on my clothes?
    The National Institute for Occupational Safety and Health (NIOSH) recommends that workers avoid bringing silica dust home from work by:
    • Changing into disposable or washable work clothes at the worksite.
    • Showering (if possible) and changing into clean clothes before leaving the worksite to prevent contamination of other work areas, cars, and homes.
    • Parking your car where it will not be contaminated with silica.

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  10. What should employers do to protect their employees?
    Planning is essential to reducing exposures and protecting workers. Paragraph (g) of the OSHA Standard (§1926.1153 Respirable Crystalline Silica) requires employers to have a Written exposure control plan” that contains at least the following elements: “(i) A description of the tasks in the workplace that involve exposure to respirable crystalline silica; (ii) A description of the engineering controls, work practices, and respiratory protection used to limit employee exposure to respirable crystalline silica for each task;  (iii) A description of the housekeeping measures used to limit employee exposure to respirable crystalline silica; and (iv) A description of the procedures used to restrict access to work areas, when necessary, to minimize the number of employees exposed to respirable crystalline silica and their level of exposure, including exposures generated by other employers or sole proprietors.”  The standard also requires employer to “review and evaluate the effectiveness of the written exposure control plan at least annually and update it as necessary”, and designate a “competent person” to implement the plan. Note: The Silica Control Plan generated by using the "Create-A-Plan" tool can also be presented as a toolbox talk. 

    In addition, paragraph (i)(2) of the standard requires employers to train all employees – workers and supervisors – on the information in the plan, including how to identify a silica hazard, proper use and maintenance of equipment and controls, the importance of using personal protective equipment provided, and the medical surveillance procedures.  The "Create-A-Plan" section of this website is a free resource designed to help employers develop their written exposure control plan. The planning tool walks an employer through 3 critical planning steps and generates a silica control plan that can be printed, emailed, or saved.  The "Training and Other Resources" section includes silica-related instructional materials, toolbox talks, handouts, videos, and other resources employers can use to train their employees.

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  11. How do I prevent exposures and control the dust?
    Preventing the dust from becoming airborne is a good way to reduce exposures.  Water can be used to suppress the dust and vacuums can be used to capture it at the source. When water or vacuums are not feasible, or if the exposures are still high even with these controls, a NIOSH approved respirator should be used; however, respirators won’t protect those working close by.  Other ways to reduce or eliminate exposures include using different materials, such as aluminum oxide instead of sand for abrasive blasting, or using work practices that help minimize dust. The “Create-A-Plan” tool on this website provides examples by material and task for controlling dust.


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  12. What can I do to protect myself?
    It is your employer’s responsibility by law to provide a safe workplace.  This is an OSHA requirement.  However, it is a worker’s responsibility to use the equipment provided, participate in educational programs on silica, and follow his or her employer’s safety and health instructions.  NIOSH recommends that workers:
    • Become informed of the health effects of breathing silica dust and the tasks that generate this dust on the job.
    • Reduce their exposure by avoiding working in dust whenever possible, using controls provide, and wearing a respirator when needed.
    • Take advantage of health or lung screening programs offered.
    • Use good personal hygiene at work:
      • Do not eat, drink, or use tobacco products in dusty areas.
      • Wash hands and face before eating, drinking, or smoking outside dusty areas.
      • Change into disposable or washable work clothes at the worksite.
      • Shower (if possible) and change into clean clothes before leaving the worksite to prevent contamination of other work areas, cars, and homes.
      • Park cars where they will not be contaminated with silica.
    To learn more read “Silicosis: Learn the Facts!”


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  13. Where can I find out about silica related rules and regulations?
    OSHA is the primary source for information on regulations that cover silica exposures and measures employers are required to take to protect their employees. In March 2016 OSHA issued the new silica standard for the construction industry. To learn more go to OSHA Silica Standard for Construction



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  14. Where can I find help in my area on silica?
    OSHA offers free and confidential advice to small and medium-sized business through an On-site Consultation Program. According to OSHA, the “On-site Consultation services are separate from enforcement and do not result in penalties or citations. Consultants from state agencies or universities work with employers to identify workplace hazards, provide advice on compliance with OSHA standards, and assist in establishing safety and health management systems.”  To learn more visit OSHA On-Site Consultation



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  15. If my task isn't on Table 1, what do I have to do to comply with the standard?
    OSHA offers three methods an employer can choose from to demonstrate compliance and assess employee exposure. An employer can use one of the three or any combination of them to ensure their employees are protected. The options are:
    • Table 1: includes pre-defined tasks and specified control methods. An employer that fully implements an equipment-control option on Table 1 for a task will not have to perform air monitoring for that task.
    • Performance or 'Objective Data': includes air monitoring data compiled by the employer or third parties, such as universities, trade associations, or manufacturers, which is sufficient to accurately characterize exposure to prove the control method used reduces silica dust exposure below the permissible exposure level (PEL) of 50 μg/m3 over an 8-hour time weighted average (TWA). The data relied on us must reflect conditions that are similar or worse than the employers current worksite conditions.
    • Scheduled Air Monitoring program: assesses exposure by implementing a scheduled air monitoring program to ensure employees are not exposed above the PEL.  When this option is used, an employer is required to implement an air monitoring program when workers are exposed over the Action Level (AL) of 25 μg/m3 over an 8-hour TWA, and implement control methods.


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  16. If my task is listed on Table 1, do I have to follow Table 1?
    It is important to note that for tasks that are included on Table 1, employers can choose to use the equipment/control options in Table 1 or they can use one of the alternative exposure control methods (performance or objective data, and scheduled air monitoring) to demonstrate compliance.



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  17. When do respirators need to be used and what type should be used?
    Personal protective equipment, including respirators, should be the last option to prevent a silica exposure. Silica dust should be controlled at the point of origin through the use of vacuum or water controls. However, if using engineering and work practice controls are not enough to reduce the exposure to below the PEL, respirators may be required. 

    The types of respirators required will depend on the task and degree of protection needed. Any respirator used will fall under OSHA’s respiratory protection standard. Please see OSHA’s website on respiratory protection for more information on the right respirators for your job tasks and how to comply with the OSHA respiratory protection standard, https://www.osha.gov/SLTC/respiratoryprotection/index.html. Table 1 of the silica standard includes respirator requirements for certain tasks and under certain conditions.



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  18. How do I clean dust on surfaces?
    Dust should always be cleaned by using wet methods, a HEPA vacuum or another method which effectively minimizes dust exposure. Dry sweeping or dry brushing is NOT allowed unless other methods are not feasible.



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  19. What is a competent person under the standard and what are they responsible for?
    A “competent person” is defined in OSHA’s silica standard for construction as “an individual who is capable of identifying existing and foreseeable respirable crystalline silica hazards in the workplace and who has authorization to take prompt corrective measures to eliminate or minimize them. The competent person must have the knowledge and ability necessary to fulfill the responsibilities set forth in paragraph (g) of this section.”



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  20. Do I need to provide all of my employees with medical surveillance?
    OSHA's silica standard for construction only requires employers to offer a medical examination to workers who will be required to wear a respirator for 30 or more days per year when performing work covered by the standard. Workers that fall into this category must be given the opportunity to have the examination required under the standard within 30 days after the initial assignment of work “unless the employee has received a medical examination that meets the requirements … within the last three years.” If the employee can demonstrate that they have already had an exam within the last three years, the employer does not have to offer another medical exam.



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