Until a final silica standard is issued, there are several OSHA standards that employers are required to comply with that can help protect workers exposed to silica dust. For example OSHA's:
- General Safety and Health Provisions Standard (1926.20) addresses the employee’s general right to a safe workplace.
- Gases, Vapors, Fumes, Dusts and Mists Standard (1926.55(a)) lists the airborne levels of substances that would make a workplace hazardous.
- The Ventilation Standard (1926.57) must be consulted for specific requirements about removing silica dust from a worker’s breathing zone.
- For worker training requirements about silica hazards, the Hazard Communication Standard (1926.59) applies, which is identical to 1910.1200.
- If respirators are required on-the-job, then employers must comply with the OSHA Respiratory Protection Standard (1926.103), which is identical to 1910.134.
The crystalline silica permissible exposure limits (PELs) for the construction industry at 29 CFR 1926.55(a) is expressed in terms of millions of particles per cubic foot (mppcf). This PEL is based on a particle count method now considered obsolete and replaced by respirable mass (gravimetric) sampling, which has results reported in milligrams per cubic meter (mg/m3). In contrast with the construction PEL, the crystalline silica PELs for general industry are based on gravimetric sampling and are the only methods currently available to OSHA compliance personnel. Since the construction and maritime PELs are expressed in terms of mppcf, the results of the gravimetric sampling must be converted to an equivalent mppcf value.
In order to determine a formula for converting from mg/m3 to mppcf, OSHA requested assistance from the National Institute for Occupational Safety and Health (NIOSH). Based on its review of published studies comparing the particle count and gravimetric methods, NIOSH recommended a conversion factor of 0.1 mg/m3 respirable dust to 1 mppcf. OSHA has determined that this conversion factor should be applied to silica sampling results used to characterize exposures in construction operations. Click here for examples of how the conversion factor should be applied to enforce the current PEL for crystalline silica (quartz) in the construction industry, or learn more at Appendix E of the OSHA National Emphasis Program for Crystalline Silica.
In addition, OSHA standard 1926.55(b) requires employers to first implement administrative and engineering controls to achieve compliance with permissible exposure limits before using personal protective equipment and other protective measures.
1926 Subpart C - General Safety and Health Provisions
- 1926.20 - General safety and health provisions
- 1926.21 - Safety training and education
- 1926.25 - Housekeeping
- 1926.27 - Sanitation
- 1926.28 - Personal protective equipment
- 1926.33 - Access to employee exposure and medical records
1926 Subpart D - Occupational Health and Environmental Controls
- 1926.51 - Sanitation
- 1926.51(f) and (g)
- 1926.55 - Gases, vapors, fumes, dusts, and mists, and Appendix A
- 1926.55 (a)
- 1926.57 - Ventilation
- 1926.57 (a) and (b)
- 1926.59 - Hazard Communication
1926 Subpart E - Personal Protective and Life Saving Equipment
- 1926.95 - Criteria for personal protective equipment
- 1926.103 (1910.134) - Respiratory protection
For specific information on OSHA standards that apply to silica go to OSHA Safety and Health Topics, Silica, Crystalline. For a complete list of OSHA standards applicable to the construction industry click here.
If you are located in one of the states or territories with an OSHA-approved State Plan, be sure to check the standards and enforcement policies in your state.