A Guide to OSHA’s Updates to the Hazard Communication Standard

The Occupational Safety and Health Administration (OSHA) has revised its?Hazard Communication Standard (HCS). The changes were published on May 20, 2024, and will take effect July 19, 2024.

What’s changing?

OSHA proposed its latest round of changes to the HCS in 2021. These changes are meant to keep pace with?Globally Harmonized System of Classification and Labeling of Chemicals (GHS) Revision No. 7. The GHS standardizes how chemical manufacturers, importers and distributors classify chemical hazards and communicates those hazards so everyone can understand them. Harmonized classification and labeling are essential in a global supply chain.

The last time OSHA updated the HCS was in 2012. It incorporated elements of GHS Revision No. 3.

OSHA’s changes affect the entire HCS, including appendices, definitions, chemical classifications, and health and physical hazards. Many changes relate to how chemicals are evaluated and classified. This is something chemical manufacturers, importers and distributors do.

Even if your business doesn’t evaluate chemicals, you should familiarize yourself with these revisions. Changes in how a chemical is classified also affect its label, safety data sheet (SDS) information and pictogram. You’ll need to educate your employees on these changes.

The following summarizes key changes in OSHA’s “Final Rule to Amend the Hazard Communication Standard.”

Changes to definitions

OSHA changed the definitions in subsection?1910.1200(c). They include the following:

Hazard classification of chemicals

OSHA added text to hazard classification section?1910.1200(d). Chemical manufacturers, importers and distributors are responsible for classifying chemicals. When classifying a chemical, they should consider the hazards that can exist under normal use and in foreseeable emergencies. They should include risks associated with changes to the chemical’s physical form or resulting from a reaction with other chemicals under normal conditions of use.

Labels and other forms of warning

OSHA added text in section?1910.1200(f). A summary of these changes is below:

• Regarding chemical hazards not otherwise classified (HNOC), OSHA added that HNOC and “hazards resulting from a reaction with other chemicals under normal conditions of use” don’t have to be addressed on the container.
• Any chemicals requiring labels, tags or markings must also include the date the chemical was released for shipment.
• When a chemical manufacturer, importer or distributor moves large amounts of dangerous chemicals, the warning label can be put directly on the container or sent electronically or with shipping documents. The idea is that workers receiving the shipment will have immediate access to the warning label in printed form.
• If the Department of Transportation (DOT) already requires a particular pictogram on a shipped container’s label, it should use the DOT’s pictogram, not OSHA’s.

Changes to the trade secrets section

OSHA replaced “percentage of composition” with “concentration or concentration range” throughout. It also replaced “physician or nurse” with “PLHCP.”

Changes to the HCS appendices

OSHA made significant changes to the HCS appendices in this update. The changes are addressed below, broken down by each appendix:

• Appendix A — Health Hazard Criteria (Mandatory)
• Appendix B — Physical Criteria (Mandatory)
• Appendix C — Allocation of Label Elements (Mandatory)
• Appendix D — Safety Data Sheets (Mandatory)
• Appendix E — Definition of Trade Secret (Mandatory)
• Appendix F — Guidance for Hazard Classifications Re: Carcinogenicity (Non-Mandatory)

Appendix A — Health Hazard Criteria

Appendix A is a substantial guideline on identifying and characterizing health hazards. It defines chemical health hazards and suggests they can cause the following health problems:

• Acute toxicity (through any route of exposure)
• Skin corrosion or irritation
• Eye damage or irritation
• Respiratory or skin sensitization
• Germ cell mutagenicity
• Carcinogenicity
• Reproductive toxicity
• Target organ toxicity (through single or repeated exposure)
• Aspiration hazard

It also explains how to classify these hazards using recommended or alternative test methods and criteria for mixtures. It offers updated classification systems to reduce animal testing for some chemicals. For example, in the case of classifying inhalation toxicity, OSHA suggests chemical evaluations consider data gathered from:

• Expert judgment
• Workplace exposures
• Testing done in a tube or dish (in vitro)
• Existing animal testing

The subsections can help you assess and categorize the severity and likelihood of each type of hazard. For example, OSHA lists five hazard categories for acute toxicity, from one (fatal or toxic substances) to five (may be harmful if exposed).

OSHA made changes to Appendix A, including the following:

Appendix B — Physical Criteria

Appendix B gives detailed physical criteria for classifying hazardous chemicals. This information is mandatory for all workplaces that handle hazardous materials. It is designed to ensure workers are aware of and adequately protected against workplace hazards.

The section is broken down into three subsections. The subsections explain different aspects of classifying hazardous chemicals based on physical properties:

• Flammable liquids define the various categories of flammable liquids based on flash point and boiling point.
• Gases under pressure distinguish between four categories of gases: compressed gas, liquefied gas, refrigerated liquefied gas and dissolved gas.
• Chemicals under pressure outline the definitions and classification of aerosols, gases and desensitized explosives.

OSHA made changes to Appendix B, including:

Appendix C — Allocation of Label Elements

Appendix C provides instructions on assigning appropriate label elements to hazardous products, including the following:

• Allocation procedure. This section outlines the elements of labels that chemical manufacturers, importers and distributors must follow.
• Signal words. You can use only one signal word per label: “danger” or “warning.” Danger is for the most severe threat. Warning is for less severe hazards.
• Hazard statements. Hazard statements describe the nature and degree of a chemical’s hazard. A specific statement is assigned to the chemical depending on its hazard class and category.
• Pictograms. Pictograms are a symbol inside a diamond with a red border. They convey certain health, physical and environmental information. OSHA has created?pictograms for specific chemical hazards.
• Precautionary statements. Precautionary statements recommend measures to minimize or prevent adverse effects from exposure, improper storage or handling of hazardous products.
• Precedence of label elements. If there isn’t enough space on a label to include all the relevant signal words, pictograms and hazard statements, this section says what to include and in what order.

OSHA made changes to Appendix C, including:

Appendix D — Safety Data Sheets

Appendix D outlines the 16 sections an SDS must contain. OSHA made changes to Appendix D, including:

Appendix E?— Definition of “Trade Secret”

Appendix E sets guidelines for handling proprietary information about chemical compilations considered business trade secrets.

A trade secret could be a formula, pattern, device or compilation a business uses and keeps confidential to give it an advantage over its competitors. Companies may not want to disclose the chemical formula for their product on a label or an SDS. They’d need to get permission from OSHA. This section details ways to handle trade secrets, including disclosing them for evaluation.

OSHA did not change Appendix E.

Appendix F?— Guidance for Hazard Classifications Re: Carcinogenicity

Appendix F is not mandatory and only provides additional guidance on carcinogenicity. The required criteria for classifying a chemical’s carcinogenicity appear in Appendix A.6 of the HCS.

OSHA did not change Appendix F.

Effective dates for the 2024 changes

The 2024 HCS changes have the following compliance dates:

• Chemical manufacturers, importers and distributors evaluating substances?have until Jan. 19, 2026, to update their evaluation standards, labels and SDSs.
• Employers who use chemical substances must update their alternate labeling systems, hazard communication programs (including SDSs and chemical inventories) and train employees on newly identified or reclassified chemical hazards by July 20, 2026.
• Chemical manufacturers, importers and distributors evaluating mixtures?have until July 19, 2027, to update their evaluation standards, labels and SDSs.
• Employers who use chemical mixtures must update their alternate labeling systems, hazard communication programs (including SDSs and chemical inventories) and train employees on newly identified or reclassified chemical hazards by Jan. 19, 2028.

OSHA’s changes revise the HCS, impacting how chemical hazards are classified and conveyed through labeling. Over the next two years, chemical manufacturers, importers and distributors will adapt to chemical labels and SDS changes. Some chemical manufacturers will be quicker than others to adapt.

Look out for updated SDSs and labels.

Review your training and hazard communication program

OSHA requires employers to have a current written hazard communication program.

• Make sure your hazard communication program includes a chemical inventory and documented employee training.
• Train your employees on the updated chemical hazards, safety measures, SDSs, pictograms and labels. Ensure they know where your SDSs and chemical lists are stored.
• Retrain employees as you receive new SDSs and labels, before using new chemicals or when chemicals are reclassified.
• Ask the chemical manufacturer or supplier to highlight changes on the SDSs for your workplace chemicals.
• If you use SDS management software, ask your account manager for guidance on updates.

When the changes take effect on July 19, 2024, you’ll be ready to update your training and HCS programs.