This analysis describes the federal Occupational Safety and Health Administration's (OSHA) hazard communication (HazCom), or worker "right-to-know," requirements for general industry and construction workplaces, including OSHA's adoption of the Globally Harmonized System of Classification and Labelling of Chemicals (GHS). OSHA's HazCom rule for the construction industry adopts the general industry rule by reference.

The purpose of HazCom is to address the issue of classifying the potential hazards of chemicals and to ensure that employers and employees can identify and understand hazardous chemicals in their workplace, the physical and health hazards associated with them, and how to take protective action.

WHAT AND WHO ARE REGULATED?

29 CFR 1910.1200(b)

HazCom applies to almost every organization and employer covered by OSHA regulations. It applies to manufacturers, importers, and distributors of hazardous chemicals, and to employers with employees exposed or potentially exposed to hazardous chemicals in general industry workplaces, shipyards, marine terminals, longshore operations, construction sites, and certain agricultural workplaces.

CHEMICAL MANUFACTURERS AND IMPORTERS

HazCom requires chemical manufacturers and importers to evaluate and classify the hazardous chemicals that they produce or import in terms of their physical and health hazards, as well as to establish hazard communication programs for their workers.

CHEMICAL DISTRIBUTORS

Distributors of hazardous chemical products must transmit the required information about hazards to employers that purchase or receive such products from them.

CHEMICAL USERS

Employers that store and use chemicals but do not produce or import them do not have to comply with the requirement to evaluate and classify the hazards of those chemicals; they must have a workplace program and a system in place for communicating information to their workers. "Use" in the context of HazCom means to package, handle, react, emit, extract, generate as a by-product, or transfer.

LABORATORIES

Laboratories that ship hazardous chemicals. Laboratory employers that ship hazardous chemicals are considered to be either chemical manufacturers or distributors. They must ensure that any containers of hazardous chemicals leaving the laboratory are properly labeled, tagged, or marked, and that a safety data sheet (SDS) is provided to distributors and other employers.

Laboratories that do not ship hazardous chemicals. Such laboratories must ensure that labels on incoming containers are not defaced, that SDSs are readily accessible to employees, and that employees receive hazard communication training and are provided information about the chemicals.

Laboratories where employees handle only chemicals in sealed containers are not required to maintain a written hazard communication program.

FACILITIES THAT HANDLE SEALED CONTAINERS ONLY

Employers in workplaces where employees handle only hazardous chemicals in sealed containers, such as marine cargo areas and warehouses, are not required to maintain a written hazard communication program for the chemicals. They must, however, still follow HazCom requirements for container or package labeling and availability of SDSs and must provide information and training to employees concerning chemical substances.

DEFINITIONS

29 CFR 1910.1200(c)

HazCom applies to any hazardous chemical in the workplace to which employees would normally be exposed under normal conditions or in a foreseeable emergency. The rule requires all employers that manufacture, import, distribute, or otherwise use hazardous substances to transmit the information about hazards to employees who work with those substances through a written hazard communication program, labels, SDSs, and an employee information and training program.

Under HazCom, "chemical" is defined as any substance or mixture of substances.

A “hazardous chemical” is any chemical that is classified as a physical hazard or health hazard, a simple asphyxiant, combustible dust, or hazard not otherwise classified (HNOC).

A "mixture" is a combination or a solution composed of two or more substances in which they do not react.

Examples of a "foreseeable emergency" include control equipment failures and ruptures in containers but do not include chemical releases resulting from accidental fires. HazCom covers both physical hazards (such as flammability) and health hazards (such as irritation, lung damage, and cancer). Most chemicals used in the workplace have some hazard potential and, thus, will be covered by the rule.

"Classification" means to identify the relevant data regarding the hazards of a chemical; to review those data to ascertain the hazards associated with the chemical; and to decide whether the chemical will be classified as hazardous according to the definition of hazardous chemical. In addition, classification for health and physical hazards includes the determination of the degree of hazard, where appropriate, by comparing the data with the criteria for health and physical hazards.

"Hazard category" means the division of criteria within each hazard class, e.g., oral acute toxicity and flammable liquids include four hazard categories. These categories compare hazard severity within a hazard class and should not be taken as a comparison of hazard categories more generally.

"Hazard class" means the nature of the physical or health hazards, e.g., flammable solid, carcinogen, and oral acute toxicity.

"Health hazard" means a chemical that is classified as posing one of the following hazardous effects:

• Acute toxicity (any route of exposure);
• Skin corrosion or irritation;
• Serious eye damage or eye irritation;
• Respiratory or skin sensitization;
• Germ cell mutagenicity;
• Carcinogenicity;
• Reproductive toxicity;
• Specific target organ toxicity (single or repeated exposure); or
• Aspiration hazard.

The criteria for determining whether a chemical is classified as a health hazard are detailed in {LNK!Type=03!RegscanDoc=db=osha&doc=000600FO.htm!}Appendix A to 29 CFR 1910.1200{/LNK!Type=03!}.

"Physical hazard" means a chemical that is classified as posing one of the following hazardous effects:

• Explosive;
• Flammable (gases, liquids, or solids);
• Aerosols;
• Oxidizer (liquid, solid, or gas);
• Self-reactive; pyrophoric (liquid or solid);
• Self-heating;
• Organic peroxide;
• Corrosive to metal;
• Gas under pressure;
• Chemicals which, in contact with water, emit flammable gas; or
• Desensitized explosive..

The criteria for determining whether a chemical is classified as a physical hazard are available in {LNK!Type=03!RegscanDoc=db=osha&doc=000600FP.htm!}Appendix B to 29 CFR 1910.1200{/LNK!Type=03!}.

EXEMPTIONS

The following are exempt from HazCom:,

• Any hazardous waste, as defined by the Solid Waste Disposal Act, as amended by the Resource Conservation and Recovery Act of 1976, as amended, when subject to regulations issued under that Act by the U.S. Environmental Protection Agency (EPA);
• Any hazardous substance, as defined by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) when the hazardous substance is the focus of remedial or removal action being conducted under CERCLA in accordance with EPA regulations.
• Tobacco or tobacco products;
• Wood or wood products, including lumber that will not be processed, where the chemical manufacturer or importer can establish that the only hazard they pose to employees is the potential for flammability or combustibility (wood or wood products that have been treated with a hazardous chemical covered by this standard, and wood which may be subsequently sawed or cut, generating dust, are not exempted);
• Articles, meaning a manufactured item other than a fluid or particle:
• That is formed to a specific shape or design during manufacture;
• That has end use function(s) dependent in whole or in part upon its shape or design during end use; and
• That under normal conditions of use does not release more than very small quantities (e.g., minute or trace amounts of a hazardous chemical), and does not pose a physical hazard or health risk to employees.
• Food or alcoholic beverages that are sold, used, or prepared in a retail establishment (such as a grocery store, restaurant, or drinking place), and foods intended for personal consumption by employees while in the workplace;
• Any drug, as defined in the Federal Food, Drug, and Cosmetic Act, when it is in solid, final form for direct administration to the patient (e.g., tablets or pills); drugs which are packaged by the chemical manufacturer for sale to consumers in a retail establishment (e.g., over-the-counter drugs); and drugs intended for personal consumption by employees while in the workplace (e.g., first-aid supplies);
• Cosmetics that are packaged for sale to consumers in a retail establishment, and cosmetics intended for personal consumption by employees while in the workplace;
• Any consumer product or hazardous substance, as defined in the Consumer Product Safety Act and Federal Hazardous Substances Act respectively, where the employer can show that it is used in the workplace for the purpose intended by the chemical manufacturer or importer of the product, and the use results in a duration and frequency of exposure that is not greater than the range of exposures that could reasonably be experienced by consumers when the product used for the intended purpose;
• Nuisance particulates where the chemical manufacturer or importer can establish that they do not pose any physical or health hazard covered under this section;
• Ionizing and nonionizing radiation; and
• Biological hazards.

The following are exempt from just the labeling requirements of HazCom:

• Any pesticide, defined in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), when subject to the labeling requirements and regulations issued by FIFRA and the Environmental Protection Agency (EPA);
• Any chemical substance or mixture, as defined in the Toxic Substances Control Act (TSCA), when subject to the labeling requirements and regulations issued under TSCA by the EPA;
• Any food, food additive, color additive, drug, cosmetic, or medical or veterinary device or product, including materials intended for use as ingredients (e.g., flavors and fragrances), as these terms are defined in the Federal Food, Drug, and Cosmetic Act or the Virus-Serum-Toxin Act of 1913, when they are subject to the labeling requirements under those Acts by either the Food and Drug Administration or the Department of Agriculture;
• Any distilled spirits (beverage alcohols), wine, or malt beverage intended for nonindustrial use, as defined in the Federal Alcohol Administration Act, when subject to the labeling requirements regulations issued under that Act by the Bureau of Alcohol, Tobacco, Firearms and Explosives;
• Any consumer product or hazardous substance, as defined in the Consumer Product Safety Act and Federal Hazardous Substances Act respectively, when subject to a consumer product safety standard or labeling requirement or regulation issued under those Acts by the Consumer Product Safety Commission; and
• Agricultural or vegetable seed treated with pesticides and labeled in accordance with the Federal Seed Act and the labeling regulations issued under that Act by the Department of Agriculture.

CONDITIONS FOR EMPLOYEE EXEMPTION FROM COVERAGE

Employees who handle hazardous chemicals in nonroutine, isolated instances are not covered for those chemicals. For example, an office employee who periodically changes the toner in a copying machine would not need information or training under HazCom for the toner.

OSHA, in this letter of interpretation, indicates that office chemicals such as white-outs, adhesives, cleaning agents, and copier chemicals, are exempt under the provisions of the rule, as consumer products. They would fall under HazCom only when they are used with greater frequency or duration than a normal consumer or for uses not intended by the manufacturer. For instance, if an employee is hired to service the machine (such as for a copier repair position), HazCom would be applicable.

29 CFR 1910.1200(d) and 29 CFR 1910.1200, Appendices A and B

The quality of the employer's hazard communication program depends on the adequacy and accuracy of the hazard evaluation and classification process—in other words, employers must know which chemicals in their workplace are hazardous.

MANUFACTURERS AND IMPORTERS

Chemical manufacturers and importers must evaluate each chemical they produce or import in order to classify the chemicals and chemical mixtures according to their physical and health hazards.

Process to classify and categorize chemical hazards. For each chemical, the chemical manufacturer or importer must determine the hazard classes and, where appropriate, the category of each class that applies to the chemical being classified.

The hazard evaluation process requires the chemical manufacturer to:

• Identify the relevant data regarding the hazards of a chemical;
• Review those data to determine the hazards associated with the chemical;
• Decide whether the chemical will be classified as hazardous according to the definition of hazardous chemical in the rule; and
• Determine the degree of hazard where appropriate by comparing the data with the criteria for health and physical hazards.

Resources to assist with classification. Manufacturers and importers must identify and consider the full range of available scientific literature and other evidence concerning the potential hazards of a chemical or chemical mixture. There is no requirement to test the chemical to determine how to classify its hazards.

OSHA has provided classifiers with the option of relying on the classification listings of the International Agency for Research on Cancer and the National Toxicology Program to make classification decisions regarding carcinogenicity rather than applying the criteria themselves.

Chemical mixtures. Chemical manufacturers and importers evaluating chemical mixtures must follow the procedures described in Appendices A and B of the rule to determine when mixtures of the classified chemicals are covered by hazard communication requirements. They may rely on the information provided on the current SDSs of the individual ingredients, except where they know or should know through reasonable diligent review that the SDS misstates or omits required information.

29 CFR 1910.1200(f) and 29 CFR 1910.1200, Appendix C

Chemical manufacturers, importers, and distributors must label every hazardous chemical container with key information on the substance it contains, and worker training must include an explanation of the labeling system.

Companies that manufacture or import chemicals must create the standardized label for a particular chemical that includes harmonized signal word, pictogram, and hazard statement for each hazard class and category. Precautionary statements must also be provided.

The employer that uses hazardous chemicals must ensure that each hazardous chemical covered by Hazcom has an appropriate label that remains firmly attached and legible; just as importantly, the employer must make sure that all exposed employees know how to read the label and use the information it conveys to protect themselves.

For additional details, see the national HazCom Labels analysis.

29 CFR 1910.1200(g) and 29 CFR 1910.100, Appendix D

Manufacturers, importers, or distributors must provide an SDS to their customers for each hazardous chemical at the time of the first shipment of the chemical.

The SDS is a standardized 16-section document prepared by the manufacturer or importer of a chemical that describes the physical and chemical properties, physical and health hazards, routes of exposure, precautions for safe handling and use, emergency and first-aid procedures, control measures, and other information about the chemical.

For additional details, see the national analysis Safety Data Sheet.

29 CFR 1910.1200(i) and 29 CFR 1910.1200, Appendix E

A trade secret may consist of any formula, pattern, device, or compilation of information that is used in one's business and that gives him or her an opportunity to obtain an advantage over competitors that do not know or use it. In this letter of interpretation, OSHA explains when an employer can claim trade secret status and what is required for an employer to claim trade secret status of a hazardous chemical ingredient.

Chemical manufacturers, importers, or employers may withhold a chemical name, other specific identification of a chemical, or the exact percentage or concentration of the substance in a mixture from an SDS if the following conditions are met:

• The claim to withhold information as a trade secret is supported.
• Information about the properties and effects of the chemical is disclosed.
• The SDS indicates that the chemical identity and/or concentration or concentration range of composition is withheld as a trade secret.
• If the concentration or concentration range is being claimed as a trade secret then the safety data sheet provides the ingredient's concentration as one of the following prescribed ranges:
• 0.1% to 1%;
• 0.5% to 1.5%;
• 1% to 5%;
• 3% to 7%;
• 5% to 10%;
• 7% to 13%;
• 10% to 30%;
• 15% to 40%;
• 30% to 60%;
• 45% to 70%;
• 60% to 80%;
• 65% to 85%; or
• 80% to 100%.
• The chemical identity and exact concentration or concentration range of composition is made available to health professionals, employees, and designated representatives in order to protect the health of workers.

Emergency disclosure of trade secret information. If withholding trade secret information would impair the Occupational Safety and Health Administration’s (OSHA) ability to evaluate employee exposure to a harmful substance, the manufacturer or employer must provide alternative data. If a treating physician or other licensed health care professional (PLHCP) determines that the identity and/or exact concentration or concentration range of a chemical is necessary for emergency or first-aid treatment, the manufacturer or employer must immediately disclose the trade secret chemical to the PLHCP, regardless of the need for a written statement of confidentiality agreement.

Nonemergency disclosure. In nonemergency situations, the manufacturer or employer must disclose the chemical identity and/or exact concentration or concentration range to a PLHCP if the request is in writing and describes with reasonable detail the occupational health needs for the information (e.g., to conduct sampling of workplace exposure, design engineering or protective measures, provide treatment). The recipient of any trade secret information must agree in writing not to use it for any purpose other than the health needs asserted and agree not to release the information under any circumstances other than to OSHA or other entity authorized by the manufacturer or employer.

29 CFR 1910.1200(e)

Employers must develop, implement, and maintain at each workplace, a written hazard communication program that includes:

• A description of the labeling system and other forms of warning used at the facility, including shipped labels, the workplace labeling system, the person responsible for labeling, and the procedures for reviewing and updating labels in the workplace;
• The locations of safety data sheets (SDS), how to access them (including the backup system should electronic access fail), the person responsible for obtaining and maintain SDSs, and procedures to follow if a SDS is no received; and
• A description of the employee information and training program, including the designation of the person responsible for training; and
• A list of the hazardous chemicals known to be present at the facility using a product identifier that is referenced on the appropriate SDS; and
• The methods the employer will use to inform employees of the hazards of non-routine tasks (for example, the cleaning of reactor vessels), and the hazards associated with chemicals contained in unlabeled pipes in their work areas.

Multiemployer workplaces. Employers who produce, use, or store hazardous chemicals at a workplace in such a way that the employees of other employer(s) may be exposed, must also include the following in the written HazCom program:

• The methods the employer will use to provide the other employer(s) on-site with access to SDSs for each hazardous chemical the other employer(s)' employees may be exposed to while working;
• The methods the employer will use to inform the other employer(s) of any precautionary measures that need to be taken to protect employees during the workplace's normal operating conditions and in foreseeable emergencies; and
• The methods the employer will use to inform the other employer(s) of the labeling system used in the workplace.

Access. Employers must make the written hazard communication program available, upon request, to employees, their designated representatives, and OSHA personnel.

Where employees must travel between workplaces during a workshift (i.e., their work is carried out at more than one geographical location), the written HazCom program may be kept at the primary workplace facility.

29 CFR 1910.1200(h)

Employees who require training. Employees who may be exposed to hazardous chemicals in their work area must be trained.

Required frequency of training. Training must occur at the time of an employee’s initial assignment and whenever a new chemical hazard about which the employees have not been trained is introduced into the work area.

Required content of training: Employees must be provided information about:

• HazCom and its requirements under 29 CFR 1910.1200;
• The operations in their work area where hazardous chemicals are present; and
• The location and availability of the written HazCom program, including the list(s) of chemicals that must be part of the program and the safety data sheets (SDSs).

The training must also include:

• The methods and observations used to detect the presence or release of a hazardous chemical in the work area, such as monitoring conducted by the employer, continuous monitoring devices, visual appearance, or odor of hazardous chemicals when being released;
• The physical, health, simple asphyxiation, combustible dust, pyrophoric gas hazards, and other hazards not otherwise classified of the chemicals in the work area;
• The measures employees can take to protect themselves from these hazards, including specific procedures implemented by the employer, such as appropriate work practices, emergency procedures, and personal protective equipment (PPE) to be used;
• The details of the written HazCom program, including an explanation of:
• Shipped container labels;
• The workplace container labeling system used by the employer; and
• SDSs, including the order of information in the SDS and how employees can obtain and use hazard information.

Information and training may be designed to cover categories of hazards (e.g., flammability, carcinogenicity) or specific chemicals. Chemical-specific information must always be available through labels and SDSs.

According to Occupational Safety and Health Administration (OSHA) guidelines, if employees receive job instructions in a language other than English, the training and information conveyed under HazCom should also be presented in that language.

OSHA Guidelines for Employee Training

Recommended training guidelines to help pass an OSHA HazCom inspection. According to OSHA HazCom guidance materials, training can be accomplished through a combination of audiovisuals, classroom instruction, and interactive video. Training can be conducted or information provided by categories of hazard (such as carcinogens or toxic agents) rather than by specific chemical. Training is required for new physical or health hazards, not for every new chemical that enters the workplace. If, however, a newly introduced chemical does not fit into an existing hazard class or category, training for that new chemical must be provided.

A general discussion of hazardous chemicals or giving employees an SDS to read, for example, is not enough. If an OSHA inspector concludes that the training is inadequate, a more rigorous review of the company's entire compliance program will probably follow. An employer is responsible for evaluating an employee's level of knowledge concerning hazards in the workplace and the hazard communication program.

Training language guideline. According to OSHA guidelines, if employees receive job instructions in a language other than English, the training and information conveyed under HazCom should also be presented in that language.

OSHA revised the Hazard Communication Standard, effective July 19, 2024. The revisions include changes to:

• Physical hazards;
• The criteria for determining various health hazards in Appendix A to 29 CFR 1910.1200;
• The criteria for determining various physical hazards in Appendix B to 29 CFR 1910.1200;
• The shipped container label elements (e.g., hazard categories, hazard statements, precautionary statements, etc.) as they pertain to specific hazards, as presented Appendix C to 29 CFR 1910.1200; and
• The information that must be included in various sections of the SDS, as presented in Appendix D to 29 CFR 1910.1200.

Manufacturers must comply with the revised provisions of the HazCom Standard effective July 19, 2024, by:

• January 19, 2026 for substances; and
• July 19, 2027 for mixtures.

Employers must update their HazCom processes, including training, workplaces labeling, updating the written program, to account for newly identified physical, health, or other hazards no later than:

• July 20, 2026, for substances; and
• January 19, 2028, for mixtures.