Your Plant Has Until November 20 to Finish HazCom 2024

The HazCom 2024 compliance deadline for employers is November 20, 2026 for substances. By that date, plants must, as necessary, update alternative workplace labels, revise the written hazard communication program, and train workers on newly identified hazards. Mixtures follow later: suppliers by November 19, 2027, employers by May 19, 2028.

That November date was originally July 20. On January 15, 2026, OSHA announced that it was pushing back every compliance date under the revised Hazard Communication Standard (HCS 2024) by four months. The agency's extension notice said the delay was meant "to give the agency time to publish the necessary guidance materials for the regulated community to review before the revised HCS provisions take effect."

The supplier deadline for substances has already passed. Manufacturers, importers and distributors had to comply by May 19, 2026, so revised safety data sheets (SDSs) and labels should already be reaching your receiving dock. For a plant, then, the remaining work is mostly reconciliation. Your suppliers do the classification. You have to make what they sent match your labels, your written program and your training before November 20, which leaves about a month.

The dates that matter

OSHA published the final rule on May 20, 2024, and it took effect July 19, 2024, according to the agency's rulemaking page. The rule aligns the standard "primarily with the seventh revision" of the UN Globally Harmonized System (GHS). The extended compliance dates are written into 29 CFR 1910.1200(j), and the law-firm summary from Morgan Lewis and the table from VelocityEHS list the same dates.

Until the applicable date arrives, paragraph (j)(4) lets manufacturers, importers, distributors and employers "comply with either this section or § 1910.1200 revised as of July 1, 2023, or both during the transition period." For substances at your plant, that transition period ends November 20.

What the rule requires of a plant

Here is the employer obligation in 1910.1200(j)(2)(ii):

"For substances, all employers shall, as necessary, update any alternative workplace labeling used under paragraph (f)(6) of this section... and provide any additional employee training ... for newly identified physical hazard, or health hazards or other hazards covered under this section no later than November 20, 2026."

The same clause also requires employers to update the hazard communication program. That gives a plant three tasks: relabel in-house containers where needed, update the written program, and train people on hazards that are new to them. The words "as necessary" carry a lot of weight here. If a supplier's revised SDS doesn't change a product's hazards, the label and training for that product may not need to change.

The heavier analytical work belongs to suppliers. They classify the chemical, write the SDS and print the shipped-container label. J.J. Keller reported in November 2025 that OSHA expects most employers to need only minimal updates because the revisions are limited. That article came out before the extension, so the dates in it are the original ones.

Morgan Lewis's employer action list follows the same order this article does: "inventory hazardous chemicals and confirm applicability of new hazard classes; coordinate with suppliers on updated SDS and labels; review and revise written hazard communication programs; assess training gaps related to newly identified hazards; and monitor OSHA guidance materials."

Step 1: Reconcile the SDSs you have received since May 19

Start with the chemical inventory. Go through every product on the list and mark which ones now have an SDS revised under HCS 2024. For each of those, compare the new version with the one it replaces, section by section. According to IHMM's July 2026 summary, Sections 2, 3, 9, 10 and 11 change to reflect revised classifications and new terminology for physical and chemical properties. A change in Section 2 (hazard identification) is usually what drives a label or training update.

The new or changed hazard classes to look for, per VelocityEHS and IHMM:

• Flammable gases are now split into Categories 1A and 1B. Pyrophoric and chemically unstable gases fall under 1A.

• Desensitized explosives are a new hazard class with four categories.

• Non-flammable aerosols are now covered as Aerosols Category 3. Check maintenance cribs, where aerosol lubricants, cleaners and coatings tend to collect.

• Chemicals under pressure are a new category taken from GHS Revision 8.

• Hazards from changes in physical form or from reaction products. IHMM notes that HCS 2024 requires manufacturers to evaluate hazards arising from "a change in the chemical's physical form" and from "chemical reaction products associated with known or reasonably anticipated uses." Combustible dust from grinding a solid is one example. For any plant that machines, sands or grinds, this item is likely to matter most.

You may also see trade-secret claims written as "prescribed concentration ranges" rather than open-ended ranges. That changes what Section 3 looks like but does not create any work for you.

Make sure the current SDS is the one workers can get to. Paragraph (g)(8) requires employers to keep SDS copies for each hazardous chemical and to ensure they "are readily accessible during each work shift to employees when they are in their work area(s)." If you use binders on the floor, swap the pages on every shift and at every station, not only in the electronic system.

You don't necessarily have to keep the superseded SDS. Under 29 CFR 1910.1020, SDSs "need not be retained for any specified period as long as some record of the identity (chemical name if known) of the substance or agent, where it was used, and when it was used is retained for at least thirty (30) years." Archive the old version in a way that keeps that identity, location and date record.

Step 1a: Chase the SDSs that haven't arrived

Some products will still be on 2012-format SDSs. Paragraph (g)(6) requires manufacturers and importers to provide an appropriate SDS with the initial shipment, either with the containers or sent before or at the time of shipment. Keep a simple request log with the product, supplier, date requested, follow-up date and date received. Send it to purchasing, since they hold the supplier relationships. The transition clause allowed suppliers to use either version only until their own applicable date. For substances, that date was May 19, so a substance SDS still in 2012 format is worth questioning.

Step 2: Relabel secondary containers, if your system calls for it

This step mainly affects plants that use the alternative workplace labeling permitted by (f)(6)(ii): a "Product identifier and words, pictures, symbols, or combination thereof, which provide at least general information regarding the hazards of the chemicals." The November 20 relabeling duty is aimed at these in-house systems.

Walk the floor with the list of SDS changes from Step 1. Look at day tanks, spray bottles, transfer drums, parts-washer reservoirs and any other container filled from a bulk source. Wherever the hazard information changed on the new SDS, update the in-house label to match. When you handle incoming containers, remember that employers may not remove or deface existing labels unless the container is immediately marked with the required information.

Two changes will show up on incoming stock, and receiving should be told about them so they aren't flagged as nonconforming:

• Small containers. Under (f)(12), containers of 100 mL or less may carry a reduced label: product identifier, pictogram, signal word, manufacturer contact, and a statement that the full label information is on the immediate outer package. Containers of 3 mL or less may carry only the product identifier if a full label would interfere with normal use. Keep the outer packaging, or move its information to your system, before you throw it away.

• Released for shipment. When suppliers learn of significant new hazard information, they have six months to revise labels. Under the 2024 changes to (f)(11), they don't have to relabel containers already "released for shipment" as long as they send the updated label with each shipment. As a result, a drum may arrive with an older label on the container and a newer one in the paperwork. Receiving needs a procedure for applying the updated label or routing it to the right person.

Step 3: Rewrite the written program

Paragraph (e)(1) requires a written program that "at least describes how the criteria specified in paragraphs (f), (g), and (h) of this section for labels and other forms of warning, safety data sheets, and employee information and training will be met." It also has to include the list of hazardous chemicals and explain how employees are told about the hazards of non-routine tasks.

In practice, revise four sections:

• Chemical list. Reconcile it against the Step 1 inventory and note which entries have HCS 2024 SDSs.

• Labeling system. Describe the in-house labels as they will exist after Step 2, and add how receiving handles small-container labels and labels shipped separately from the container.

• SDS management. Write down the request-and-follow-up procedure from Step 1a, how SDSs are made accessible on every shift, and how superseded versions are archived under the 1910.1020 record rule.

• Training. Update the content to cover the HCS 2024 hazard classes and say what triggers retraining.

Also review the non-routine task section. Grinding, cutting or cleaning out a vessel are the kinds of jobs where hazards from physical-form changes are most likely to appear.

Step 4: Retrain the people who need it, and document it

Paragraph (h)(1) requires training "at the time of their initial assignment, and whenever a new chemical hazard the employees have not previously been trained about is introduced into their work area." Under (h)(3), training must cover:

• methods for detecting a release

• physical and health hazards, including simple asphyxiation, combustible dust and pyrophoric gas hazards

• protective measures such as work practices, emergency procedures and PPE

• the details of the site's program, its labeling system and how to use SDSs

The trigger in the text is a new hazard in a work area. Use the Step 1 results to map each newly identified hazard to the areas and jobs where the product is used, then build the session around that map. Retraining every employee is usually unnecessary. Anyone whose in-house labels changed in Step 2 should at least be shown the new label.

Keep a record of who was trained, on which products and hazards, when, and by whom. The standard text reviewed for this article does not include a dated-records requirement for HazCom training. Still, customer and registrar auditors will ask for records, and a sign-in sheet tied to a product list is the simplest way to show the work was done.

What can wait: mixtures

Most of what a plant buys (coolants, cleaners, coatings, adhesives) is a mixture, and mixtures are on a later schedule. Suppliers have until November 19, 2027. Employers have until May 19, 2028. You may see November 2027 described as "the mixtures deadline," but that is the supplier date. Your plant's mixture deadline is six months after it.

Mixture SDSs will arrive in larger numbers than the substance SDSs did, so set up the process now. If the inventory comparison, supplier request log, label walk and targeted training work for substances this fall, you can reuse them for mixtures in 2027 and 2028.

Checklist: from now to November 20

These target dates are suggestions that work back from the deadline. Adjust them to your site.

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Sources

• 29 CFR 1910.1200, Hazard Communication (OSHA)

• HCS 2024 compliance date extension (OSHA)

• OSHA QuickTakes, January 15, 2026

• OSHA's Final Rule to Amend the Hazard Communication Standard

• More Time to Comply: OSHA Pushes Back Hazard Communication Deadlines by Four Months (Morgan Lewis)

• OSHA Extends Deadlines for HazCom 2024 Compliance (VelocityEHS)

• Changes Under OSHA's GHS Revision 7 Alignment: November 2026 Next Deadline (IHMM)

• First HazCom compliance date just around the corner (J.J. Keller)

• A Refresher on the 2024 HazCom Final Rule (VelocityEHS)

• 29 CFR 1910.1020, Access to employee exposure and medical records (OSHA)