Does "Subpart Z - Toxic and Hazardous Substances" Apply to You?

This standard regulates asbestos exposure in all construction work, paragraph (c), including but not limited to the following:

• Demolition or salvage of structures where asbestos is present;
• Removal or encapsulation of materials containing asbestos;
• Construction, alteration, repair, maintenance, or renovation of structures, substrates, or portions thereof, that contain asbestos;
• Installation of products containing asbestos;
• Asbestos spill/emergency cleanup; and
• Transportation, disposal, storage, containment of and housekeeping activities involving asbestos or products containing asbestos, on the site or location at which construction activities are performed.

Coverage under this standard is based on the nature of the work operation involving asbestos exposure. It does not apply to asbestos-containing asphalt roof coatings, cements and mastics.

Based on the above information, are your employees conducing construction work involving exposure to asbestos? If yes, then you need to comply with the asbestos standard. It provides the requirements pertaining to permissible exposure limits (PELs), multi-employer worksites, regulated areas, exposure assessments and monitoring, methods of compliance (i.e., engineering controls, work practice controls), respirator program (i.e., reference the general industry respiratory protection standard), protective clothing, hygiene facilities and practices for employees (reference the general industry sanitation standard), hazard communication program (reference the general industry hazard communication standard), signs and labels, employee information and training, housekeeping, medical surveillance, recordkeeping (reference the general industry standard on access to employee exposure and medical records), competent person, and mandatory and non-mandatory appendices (i.e., medical questionnaires, work practices and engineering controls for class I asbestos operations). 

The appendices for this standard are as follows: appendix A provides the procedure for analyzing air samples for asbestos and specifies quality control procedures that must be implemented by laboratories performing the analysis; appendix B provides detailed procedures for asbestos sampling and analysis; appendix D provides the medical questionnaires; appendix E provides the interpretation and classification of chest roentgenograms; appendix F provides work practices and engineering controls for automotive brake and clutch inspection, disassembly, repair and assembly; appendix H provides substance technical information for asbestos; appendix I provides medical surveillance guidelines for asbestos; appendix J provides the smoking cessation program information for asbestos; and appendix k pertains to polarized light microscopy of asbestos.

This standard also provides definitions including:

Asbestos - Includes chrysotile, amosite, crocidolite, tremolite asbestos, anthophyllite asbestos, actinolite asbestos, and any of these minerals that has been chemically treated and/or altered.

Asbestos-containing material (ACM) - Any material containing more than one percent asbestos.

Competent person - In addition to the definition in paragraph (f), means one who is capable of identifying existing asbestos hazards in the workplace and selecting the appropriate control strategy for asbestos exposure, who has the authority to take prompt corrective measures to eliminate them, as specified in 29 CFR 1926.32(f): in addition, for Class I and Class II work who is specially trained in a training course which meets the criteria of EPA's Model Accreditation Plan (40 CFR 763) for supervisor, or its equivalent and, for Class III and Class IV work, who is trained in a manner consistent with EPA requirements for training of local education agency maintenance and custodial staff as set forth at 40 CFR 763.92 (a)(2).

Time weighted average (TWA) permissible exposure limit (PEL) - The employee's average airborne exposure in any 8-hour work shift of a 40-hour work week which shall not be exceeded.

Presumed asbestos containing material - Thermal system insulation and surfacing material found in buildings constructed no later than 1980. 

Related information can be found on the A-Z safety and health topics pages for asbestos, personal protective equipment, hazard communication and respiratory protection. 

If yes, then you need to comply with the standard on coal tar pitch volatiles; interpretation of term. It states "As used in 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the distillation residues of coal, petroleum (excluding asphalt), wood, and other organic matter. Asphalt (CAS 8052-42-4, and CAS 64742-93-4) is not covered under the "coal tar pitch volatiles" standard."

Note: The requirements applicable to construction work are identical to the general industry standard for coal tar pitch volatiles; interpretation of term.

The 13 carcinogens include the following:

1. 4-Nitrobiphenyl;
2. alpha-Naphthylamine;
3. methyl chloromethyl ether;
4. 3,3'-Dichlorobenzidine (and its salts);
5. bis-Chloromethyl ether;
6. beta-Naphthylamine;
7. Benzidine;
8. 4-Aminodiphenyl;
9. Ethyleneimine;
10. beta-Propiolactone;
11. 2-Acetylaminofluorene;
12. 4-Dimethylaminoazo-benzene; and
13. N-Nitrosodimethylamine.

Do you have one of the chemicals listed above? If yes, then you need to comply with the standard on 13 carcinogens. It applies to any area in which the 13 carcinogens are manufactured, processed, repackaged, released, handled, or stored, but shall not apply to transshipment in sealed containers, except for the labeling requirements. It does not apply to the following:

• Solid or liquid mixtures containing less than 0.1 percent by weight or volume of 4-Nitrobiphenyl; methyl chloromethyl ether; bis-chloromethyl ether; beta-Naphthylamine; benzidine or 4-Aminodiphenyl; and
• Solid or liquid mixtures containing less than 1.0 percent by weight or volume of alpha-Naphthylamine; 3,3'-Dichlorobenzidine (and its salts); Ethyleneimine; beta-Propiolactone; 2-Acetylaminofluorene; 4-Dimethylaminoazobenzene, or N-Nitrosodimethylamine.

Note: The requirements applicable to construction work are identical to the general industry standard for 13 carcinogens.

This standard provides the requirements for regulated areas, respirator program (reference the respiratory protection standard), contamination control, medical surveillance, hygiene facilities and practices (reference the sanitation standard), hazard communication program (reference the hazard communication standard), signs and labels, training and education, and records (reference the standard on access to employee exposure and medical records). It also provides definitions such as:

Authorized employee means an employee whose duties require him to be in the regulated area and who has been specifically assigned by the employer.

Regulated area means an area where entry and exit is restricted and controlled.

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, eyewash stations and emergency showers, hazard communication, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the standard on vinyl chloride as it provides the requirements for the control of employee exposure to vinyl chloride (chloroethene). It applies to the manufacture, reaction, packaging, repackaging, storage, handling or use of vinyl chloride or polyvinyl chloride, but does not apply to the handling or use of fabricated products made of polyvinyl chloride. The standard also applies to the transportation of vinyl chloride or polyvinyl chloride except to the extent that the Department of Transportation may regulate them. Note: The requirements applicable to construction work are identical to the general industry standard for vinyl chloride.

This standard provides the permissible exposure limit (PEL) along with requirements for exposure monitoring, regulated areas, methods of compliance (i.e., engineering controls, work practice controls, personal protective controls), respirator program (reference the respiratory protection standard), hazardous operations, emergency situations, training, medical surveillance, hazard communication program (reference the hazard communication standard), signs and labels, and records (reference the standard on access to employee exposure and medical records). It also provides definitions such as:

Vinyl chloride means vinyl chloride monomer.

Action level means a concentration of vinyl chloride of 0.5 ppm averaged over an 8-hour workday.

Hazardous operation means any operation, procedure, or activity where a release of either vinyl chloride liquid or gas might be expected as a consequence of the operation or because of an accident in the operation, which would result in an employee exposure in excess of the permissible exposure limit.

Related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, eyewash stations and emergency showers, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the inorganic arsenic standard. It applies to all occupational exposures to inorganic arsenic. This standard does not apply to employee exposures in agriculture or resulting from pesticide application, the treatment of wood with preservatives or the utilization of arsenically preserved wood. Note: The requirements applicable to construction work are identical to the general industry standard for inorganic arsenic.

This standard provides the permissible exposure limit along with requirements for exposure monitoring, regulated areas, methods of compliance (i.e., engineering controls, work practice controls, written compliance plan), respirator program (reference the respiratory protection standard), protective work clothing and equipment (reference the standard on eye and face protection), signs and labels, hygiene facilities and practices (reference the sanitation standard), hazard communication program (reference the hazard communication standard), medical surveillance, information and training, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for this standard are as follows: appendix A provides the inorganic arsenic substance information sheet; appendix B provides the substance technical guidelines; and appendix C provides medical surveillance guidelines. This standard also provides definitions such as:

Inorganic arsenic means copper aceto-arsenite and all inorganic compounds containing arsenic except arsine, measured as arsenic (As).

Action level means a concentration of inorganic arsenic of 5 micrograms per cubic meter of air (5 ug/m(3)) averaged over any eight (8) hour period. 

Related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, hierarchy of controls and respiratory protection.

If yes, you need to comply with the standard on beryllium as it applies to occupational exposure to beryllium in all forms, compounds, and mixtures in construction. It does not apply to:

This standard provides the permissible exposure limit (PEL) and requirements for exposure assessments, exposure monitoring, methods of compliance (i.e., written exposure control plan, engineering controls, work practice controls), respirator program (reference the general industry standard for respiratory protection), personal protective clothing and equipment (reference subpart E - personal protective and life saving equipment ), hygiene areas and practices (reference the sanitation standard), hazard communication program (reference the general industry standard for hazard communication), signs and labels, housekeeping, medical surveillance, medical removal, information and training, and recordkeeping (reference the general industry standard for access to employee exposure and medical records). This standard also provides definitions such as: 

Action level means a concentration of airborne beryllium of 0.1 micrograms per cubic meter of air (μg/m³) calculated as an 8-hour time-weighted average (TWA).

Competent person means an individual who is capable of identifying existing and foreseeable beryllium 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, ability, and authority necessary to fulfill the responsibilities set forth in paragraph (e) of this standard.

Additional information can be found on the A-Z safety and health topics pages for beryllium, personal protective equipment, hazard communication, hierarchy of controls and respiratory protection. In addition, occupational exposure to beryllium falls within the OSH Division health hazards special emphasis program.

If yes, you need to comply with the chromium VI standard as it applies to occupational exposures to chromium (VI) in all forms and compounds in construction, except: 

• Exposures that occur in the application of pesticides regulated by the Environmental Protection Agency or another Federal government agency (e.g., the treatment of wood with preservatives);
• Exposures to portland cement; or
• Where the employer has objective data demonstrating that a material containing chromium or a specific process, operation, or activity involving chromium cannot release dusts, fumes, or mists of chromium (VI) in concentrations at or above 0.5 µg/m³ as an 8-hour time-weighted average (TWA) under any expected conditions of use.

This standard provides requirements pertaining to permissible exposure limits, exposure determination, methods of compliance (i.e., engineering controls, work practice controls), respirator program (reference the general industry standard for respiratory protection), hygiene areas and practices (reference the sanitation standard), protective work clothing and equipment, labels, hazard communication program (reference the general industry hazard communication standard), medical surveillance, employee information and training, and recordkeeping (reference the general industry standard on access to employee exposure and medical records). This standard also provides definitions such as: 

Action level means a concentration of airborne chromium (VI) of 2.5 micrograms per cubic meter of air (2.5 µg/m³) calculated as an 8-hour time-weighted average (TWA). 

Chromium (VI) [hexavalent chromium or Cr(VI)] means chromium with a valence of positive six, in any form and in any compound. 

Emergency means any occurrence that results, or is likely to result, in an uncontrolled release of chromium (VI). If an incidental release of chromium (VI) can be controlled at the time of release by employees in the immediate release area, or by maintenance personnel, it is not an emergency. 

Employee exposure means the exposure to airborne chromium (VI) that would occur if the employee were not using a respirator. 

Additional information can be found on the A-Z safety and health topics pages for chromium VI, personal protective equipment, hazard communication, eyewash stations and emergency showers, hierarchy of controls and respiratory protection. In addition, occupational exposure to hexavalent chromium falls within the OSH Division health hazards special emphasis program.

If yes, then you need to comply with the cadmium standard as it applies to all construction work where an employee may potentially be exposed to cadmium. Construction work is defined as work involving construction, alteration and/or repair, including but not limited to the following:

• Wrecking, demolition or salvage of structures where cadmium or materials containing cadmium are present;
• Use of cadmium containing-paints and cutting, brazing, burning, grinding or welding on surfaces that were painted with cadmium-containing paints;
• Construction, alteration, repair, maintenance, or renovation of structures, substrates, or portions thereof, that contain cadmium, or materials containing cadmium;
• Cadmium welding; cutting and welding cadmium-plated steel; brazing or welding with cadmium alloys;
• Installation of products containing cadmium;
• Electrical grounding with cadmium welding, or electrical work using cadmium-coated conduit;
• Maintaining or retrofitting cadmium-coated equipment;
• Cadmium contamination/emergency cleanup; and
• Transportation, disposal, storage, or containment of cadmium or materials containing cadmium on the site or location at which construction activities are performed.

This standard provides the permissible exposure limit (PEL) and the requirements for exposure monitoring, regulated areas, methods of compliance (i.e., engineering controls, work practice controls, written compliance program), respirator program (reference the general industry respiratory protection standard), emergency situations, protective work clothing and equipment (reference the general industry standard on eye and face protection), hygiene areas and practices (reference the sanitation standard), hazard communication program (reference the general industry hazard communication standard), housekeeping, signs and labels, medical surveillance, employee information and training, observation of monitoring, and recordkeeping (reference the general industry standard on access to employee exposure and medical records). 

The appendices for cadmium are as follows: appendix A provides the substance safety data sheet; appendix B provides the substances technical guidelines for cadmium; appendix D pertaining to occupational health history interview with reference to cadmium exposure; appendix E provides cadmium in workplace atmospheres; and appendix F pertains to nonmandatory protocol for biological monitoring. This standard also provides definitions such as:

Action level (AL) is defined as an airborne concentration of cadmium of 2.5 micrograms per cubic meter of air (2.5 ug/m(3)), calculated as an 8-hour time-weighted average (TWA). 

High-efficiency particulate air (HEPA) filter means a filter capable of trapping and retaining at least 99.97 percent of mono-dispersed particles of 0.3 micrometers in diameter. 

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the standard on benzene as it applies to all occupational exposures to benzene. This standard does not apply to:

• The storage, transportation, distribution, dispensing, sale or use of gasoline, motor fuels, or other fuels containing benzene subsequent to its final discharge from bulk wholesale storage facilities, except that operations where gasoline or motor fuels are dispensed for more than 4 hours per day in an indoor location are covered by this standard.
• Loading and unloading operations at bulk wholesale storage facilities which use vapor control systems for all loading and unloading operations, except for the provisions of hazard communication as incorporated into this standard and the emergency provisions of this standard.
• The storage, transportation, distribution or sale of benzene or liquid mixtures containing more than 0.1 percent benzene in intact containers or in transportation pipelines while sealed in such a manner as to contain benzene vapors or liquid, except for the provisions of hazard communication as incorporated into this section and the emergency provisions of this standard.
• Containers and pipelines carrying mixtures with less than 0.1 percent benzene and natural gas processing plants processing gas with less than 0.1 percent benzene.
• Work operations where the only exposure to benzene is from liquid mixtures containing 0.1 percent or less of benzene by volume or the vapors released from such liquids after September 12, 1989; except that tire building machine operators using solvents with more than 0.1 percent benzene are covered by this standard.
• Oil and gas drilling, production and servicing operations.
• Coke oven batteries.

Note: The requirements applicable to construction work are identical to the general industry standard for benzene.

This standard provides the permissible exposure limit (PEL) along with other requirements such as regulated areas, exposure monitoring, methods of compliance (i.e., engineering controls, work practice controls, written compliance program), respirator program (reference the respiratory protection standard), protective work clothing and equipment (reference the standard on eye and face protection), hygiene facilities and practices (reference the sanitation standard), hazard communication program (reference the hazard communication standard), medical surveillance, information and training, signs and labels, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for benzene are as follows: appendix A provides the substance safety data sheet; appendix B provides the substance technical guidelines; appendix C provides the medical surveillance guidelines; and appendix D provides the sampling and analytical methods for benzene monitoring and measurement procedures. This standard also provides definitions including:

Action level means an airborne concentration of benzene of 0.5 ppm calculated as an 8-hour time-weighted average. 

Benzene (C₆H₆) (CAS Registry No. 71-43-2) means liquefied or gaseous benzene. It includes benzene contained in liquid mixtures and the benzene vapors released by these liquids. It does not include trace amounts of unreacted benzene contained in solid materials. 

Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment which may or does result in an unexpected significant release of benzene. 

Employee exposure means exposure to airborne benzene which would occur if the employee were not using respiratory protective equipment. 

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, eyewash stations and emergency showers, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the 1,2-dibromo-3-chloropropane standard as it applies to occupational exposure to 1,2-dibromo-3-chloropropane (DBCP). It does not apply to:

• Exposure to DBCP which results solely from the application and use of DBCP as a pesticide; or
• The storage, transportation, distribution or sale of DBCP in intact containers sealed in such a manner as to prevent exposure to DBCP vapors or liquid, except for emergency requirements, employee information and training, and communication of hazards required by the standard.

Note: The requirements applicable to construction work are identical to the general industry standard for 1,2-dibromo-3-chloropropane.

It provides the permissible exposure limit and requirements pertaining to regulated areas, exposure monitoring, methods of compliance (i.e., engineering controls, work practice controls, written compliance program), emergency situations (i.e., written plan), respirator program (reference the respiratory protection standard), protective work clothing and equipment (reference the standard on eye and face protection), hygiene facilities and practices (reference the sanitation standard), housekeeping, hazard communication program (reference the hazard communication standard), medical surveillance, information and training, signs and labels, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for this standard cover the following: appendix A provides the substance safety data sheet for DBCP; appendix B provides the substance technical guidelines for DBCP; and appendix C provides the Medical surveillance guidelines for DBCP. This standard also provides definitions such as:

DBCP means 1,2-dibromo-3-chloropropane, Chemical Abstracts Service Registry Number 96-12-8, and includes all forms of DBCP. 

Emergency means any occurrence such as, but not limited to equipment failure, rupture of containers, or failure of control equipment which may, or does, result in an unexpected release of DBCP. 

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, eyewash stations and emergency showers, emergency action plans, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the standard on acrylonitrile as it applies to all occupational exposures to acrylonitrile (AN). It does not apply to exposures which result solely from the processing, use, and handling of the following materials:

• ABS resins, SAN resins, nitrile barrier resins, solid nitrile elastomers, and acrylic and modacrylic fibers, when these listed materials are in the form of finished polymers, and products fabricated from such finished polymers;
• Materials made from and/or containing AN for which objective data is reasonably relied upon to demonstrate that the material is not capable of releasing AN in airborne concentrations in excess of 1 ppm as an eight (8)-hour time-weighted average, under the expected conditions of processing, use, and handling which will cause the greatest possible release; and
• Solid materials made from and/or containing AN which will not be heated above 170 deg. F during handling, use, or processing.

Note: The requirements applicable to construction work are identical to the general industry standard for acrylonitrile.

This standard provides the permissible exposure limits and the requirements pertaining to exposure monitoring, medical surveillance, regulated areas, methods of compliance (i.e., engineering controls, work practice controls, written compliance program), respirator program (reference the respiratory protection standard), protective work clothing and equipment (reference the standard on eye and face protection and general requirements), hygiene facilities and practices (reference the sanitation standard), hazard communication program (reference the hazard communication standard), information and training, emergency situations (i.e., written plan), training, signs and labels, housekeeping, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for acrylonitrile cover the following: appendix A provides the substance safety data sheet; appendix B provides the substance technical guidelines; appendix C provides the medical surveillance guidelines; and appendix D provides the sampling and analytical methods. This standard also provides definitions such as:

Acrylonitrile or AN means acrylonitrile monomer, chemical formula CH(2)=CHCN. 

Action level means a concentration of AN of 1 ppm as an eight (8)-hour time-weighted average. 

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, hierarchy of controls and respiratory protection.

If yes, you need to comply with the ethylene oxide standard as it applies to all occupational exposures to ethylene oxide (EtO). It does not apply to:

• The processing, use, or handling of products containing EtO where objective data are reasonably relied upon that demonstrate that the product is not capable of releasing EtO in airborne concentrations at or above the action level under the expected conditions of processing, use, or handling that will cause the greatest possible release.

Note: The requirements applicable to construction work are identical to the general industry standard for ethylene oxide.

It provides the permissible exposure limit and requirements pertaining to exposure monitoring, regulated areas, methods of compliance (i.e., engineering controls, work practice controls, written compliance program), respirator program (reference the respiratory protection standard), personal protective equipment (reference the standard on eye and face protection and general requirements), hygiene facilities and practices (reference the sanitation standard), hazard communication program (reference the hazard communication standard), information and training, emergency situations (reference emergency action plans and fire prevention plans), medical surveillance, training, signs and labels, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for ethylene oxide cover the following: appendix A provides the substance safety data sheet; appendix B provides the substance technical guidelines; appendix C provides the medical surveillance guidelines; and appendix D provides the sampling and analytical methods for ethylene oxide. This standard also provides the definitions such as: 

Action level means a concentration of airborne EtO of 0.5 ppm calculated as an eight (8)-hour time-weighted average.

Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment that is likely to or does result in an unexpected significant release of EtO.

Employee exposure means exposure to airborne EtO which would occur if the employee were not using respiratory protective equipment.

Ethylene oxide or EtO means the three-membered ring organic compound with chemical formula C(2)H(4)O.

Additional related information can be found on the A-Z safety and health topic pages for personal protective equipment, hazard communication, emergency action plans, fire prevention plans, eyewash stations and emergency showers, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the formaldehyde standard as it applies to all occupational exposures to formaldehyde (i.e., from formaldehyde gas, its solutions, and materials that release formaldehyde).  Note: The requirements applicable to construction work are identical to the general industry standard for formaldehyde.

It provides the permissible exposure limit and requirements pertaining to the permissible exposure limit, exposure monitoring, regulated areas, signs and labels, methods of compliance (i.e., engineering controls, work practice controls), respirator program (reference the respiratory protection standard), personal protective equipment (reference the standard on eye and face protection and general requirements), emergency situations, hygiene protection (reference the sanitation standard), housekeeping, hazard communication program (reference the hazard communication standard), information and training, emergency procedures, medical surveillance, training, signs and labels, and recordkeeping (reference the standard on access to employee exposure and medical records). 

The appendices for formaldehyde cover the following: appendix A provides the substance technical guidelines; appendix B provides the sampling strategy and analytical methods; appendix C pertains to medical surveillance, and appendix D provides the nonmandatory medical disease questionnaire. This standard also provides definitions such as:

Action level means a concentration of 0.5 part formaldehyde per million parts of air (0.5 ppm) calculated as an eight (8)-hour time-weighted average (TWA) concentration. 

Emergency is any occurrence, such as but not limited to equipment failure, rupture of containers, or failure of control equipment that results in an uncontrolled release of a significant amount of formaldehyde. 

Employee exposure means the exposure to airborne formaldehyde which would occur without corrections for protection provided by any respirator that is in use. 

Additional information can be found on the A-Z safety and health topic pages for formaldehyde, personal protective equipment, hazard communication, eyewash stations and emergency showers, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the methylene chloride standard as it applies to all occupational exposures to methylene chloride (MC) in general industry, construction and shipyard employment. Note: The requirements applicable to construction work are identical to the general industry standard for methylene chloride.

It provides the permissible exposure limit and requirements pertaining to exposure monitoring, methods of compliance (i.e., engineering controls, work practice controls, incidental leaks - reference HAZWOPER, paragraph (q)), respirator program (reference the respiratory protection standard), protective work clothing and equipment (reference the standard on eye and face protection), hygiene facilities, hazard communication program (reference the hazard communication standard), information and training, labels, medical surveillance, and recordkeeping (reference the standard on access to employee exposure and medical records). It also provides definitions such as:

Action level means a concentration of airborne MC of 12.5 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA).  

Emergency means any occurrence, such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which results, or is likely to result in an uncontrolled release of MC. If an incidental release of MC can be controlled by employees such as maintenance personnel at the time of release and in accordance with the leak/spill provisions required by paragraph (f) of this section, it is not considered an emergency as defined by this standard. 

Employee exposure means exposure to airborne MC which occurs or would occur if the employee were not using respiratory protection. 

Additional information can be found on the A-Z safety and health topic pages for methylene chloride, personal protective equipment, hazard communication, hazardous waste operations and emergency response, eyewash stations and emergency showers, hierarchy of controls and respiratory protection.

If yes, then you need to comply with the respirable crystalline silica standard. It applies to all occupational exposures to respirable crystalline silica in construction work, except where employee exposure will remain below 25 micrograms per cubic meter of air (25 μg/m³) as an 8-hour time-weighted average (TWA) under any foreseeable conditions.

This standard provides the requirements pertaining to specified exposure control methods. It also provides alternative exposure control methods including the permissible exposure limit and requirements pertaining to an exposure assessment, methods of compliance (i.e.., engineering and work practice controls, ventilation), respirator program (reference the general industry standard for respiratory protection), housekeeping, written exposure control plan, medical surveillance, hazard communication program (reference the general industry standard for hazard communication), information and training, and recordkeeping (reference the general industry standard on access to employee exposure and medical records). 

The appendices for silica cover the following: appendix A provides the methods of sample analysis and appendix B pertains to the medical surveillance guidelines. This standard also provides the definitions such as:

Action level means a concentration of airborne respirable crystalline silica of 25 μg/m³, calculated as an 8-hour TWA.

Employee exposure means the exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.

Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle size- selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality-Particle Size Fraction Definitions for Health-Related Sampling.

Additional related information can be found on the A-Z safety and health topic pages for silica, personal protective equipment, hazard communication, hierarchy of controls and respiratory protection. In addition, occupational exposure to silica falls within the OSH Division health hazards special emphasis program.