Airborne Contaminants

OSHA’s New Crystalline Silica Rule: The 6 Things You Need to Know

Date First Published on SafetySmart Compliance: September 5th, 2013
Topics: Airborne Contaminants |

agate stoneOSHA finally proposed a Crystalline Silica rule. In case you don’t have the time to read through all 757 pages of the Proposed Rule, here’s a set of FAQs explaining the key requirements and how they affect you.


Question: Why did OSHA propose the Rule?

Answer: Millions of American workers are exposed to crystalline silica, a mineral compound that gets in the air and causes fatal diseases when workers breathe it in like silicosis (scarring of the lungs), lung and other forms of cancer, as well as disabling diseases like COPD (chronic obstructive pulmonary disease). OSHA’s current crystalline silica requirements date back to 1971. The Proposed Rule is designed to update and improve protection of exposed workers.

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Question: Who does the Rule cover?

Answer: The Rule applies to you if both of these conditions are true:

1. You’re covered by the OSHA standard for:

  • General Industry;
  • Maritime; or
  • Construction.


2. You use or handle “respirable crystalline silica,” defined as airborne particles containing quartz, cristobalite and/or tridymite.

Examples of Covered Industries

  • Asphalt Roofing Materials
  • Concrete Products
  • Cut Stone
  • Dental Laboratories
  • Foundries
  • Jewelry
  • Porcelain Enameling
  • Pottery
  • Railroads
  • Ready-Mix Concrete
  • Shipyards
  • Structural Clay Products
  • Support Activities for Oil and Gas Operations

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Question: What does the Rule require?

Answer: The thrust of the Rule is to require you to take steps to limit how much crystalline silica your workers are exposed to over an average 8-hour work shift.

  • The maximum amount of exposure—Permissible Exposure Limit (PEL)—for crystalline silica will be 50 micrograms per cubic meter of air (50 μg/m3), as opposed to 100 under current rules.
  • The limit at which additional steps are required to protect workers—Action Limit—is also being cut in half from 50 μg/m3 to 25 μg/m3 .


Question: How are you supposed to keep crystalline silica within the new PEL?

Answer: There are 8 steps to take:

Step 1: Do a Crystalline Silica Exposure Assessment

Once the Rule takes effect, you must do testing of breathing air samples analyzed by a lab to determine how much crystalline silica workers are exposed to over an average 8-hour shift. Subsequent monitoring is also required if initial assessment finds exposure above the new action level of 25 μg/m3 .

Exposure Level

Subsequent Monitoring Required

Below action level


At or above action level

Repeat testing at least once every 6 months

* You also have to do exposure assessments whenever changes in production, process, control equipment, personnel or work practices that may “reasonably be expected” to create new or additional exposure at or above the action level.

Step 2: Notify Workers 

You must notify affected workers in writing of the results of the exposure assessment within 15 working days of completing it either by:

  • Giving each worker a written notice; or
  • Posting the results in an accessible location.

If assessment detects exposure above the PEL, the notification must also describe the corrective action you’re taking to get exposure to or below the PEL.

Step 3: Limit Access to High Concentration Areas

 You must take steps to limit workers’ access to areas of the workplace where concentration of crystalline silica can “reasonably be expected” to be above the PEL:

  • Option 1: Establish a regulated area  that is clearly marked, off limits to all but authorized personnel and requires respirators and/or protective clothing for entry; or
  • Option 2: Implement a written access control program that includes procedures for identifying and notifying personnel of presence and location of areas containing concentrations above the PEL and requires respirators and/or protective clothing.

Step 4: Use Engineering to Control Dust Levels

The first choice in protecting workers from crystalline silica exposure is to use engineering controls to get exposure below the PEL, including:

  • Substituting crystalline silica with less toxic materials;
  • Isolating and/or enclosing the work area to keep dusts from spreading;
  • Ventilating the air in the work area; and/or
  • Using HEPA-filter vacuums, wet methods and other methods to reduce dust.

Step 5: Provide Workers Respirators

If you can’t use engineering controls to keep exposure at or below the PEL, you must furnish workers’ respirators that meet the requirements for respiratory protection.

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Step 6: Conduct Medical Surveillance of Workers

You must provide medical surveillance of any worker exposed to crystalline silica above the PEL for 30 or more days per year. Medical surveillance must be free to the worker, be provided at a “reasonable” time and place and consist of:

  • An initial/baseline exam, including chest x-rays, medical and work histories, tuberculosis and other testing;
  • Additional exams recommended by the physician or other licensed healthcare professional; and
  • Periodic tests at least every 3 years.

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Step 7: Notify and Train Worker on Hazards

You must provide exposed workers information and training on the hazards they face and ensure that workers can demonstrate knowledge of:

  • Specific operations involving exposure above the PEL;
  • Safe work procedures, use of respirators and protective clothing and other crystalline silica exposure safety procedures;
  • What the OSHA rules require; and
  • A description of the medical surveillance program and its purpose.

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Step 8: Keep the Right Records

The Rule also requires you to maintain certain records, including:

  • Air monitoring and testing results;
  • The “objective data” you use to measure exposure; and
  • Medical surveillance records.

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Question: When does the Rule take effect?

Answer: By the end of 2015 at the earliest. Explanation: This is just a proposed Rule. OSHA has to jump through several more hoops before it can finalize the Rule and put it into effect:



90-day comment period

90 days after Rule published in Federal Register

Informal hearings

March 4, 2014

OSHA revises rule based on comments and publishes Final Rule

Fall 2014 at earliest (2015 more likely)

Final Rule takes effect

At least 30 days after Final Rule published


Engineering controls must be in place within 1 year after Rule takes effect

OSHA is also notoriously slow in moving through the process of turning proposed into final rules. Moreover, employers will get an additional 12 months after the Rule takes effect to implement the required engineering controls.


Question: How much will it cost you to comply with the Rule?

Answer: OSHA claims that the average workplace will have to spend about $1,242 to comply with the Rule–$550 if there fewer than 20 workers. The estimate is probably on the low side. However, costs will be kept down by the fact that limiting exposure to crystalline silica is required by current rules. The most important change in the new Rule are the tighter exposure limits.