OSHA published the final rule updating the Hazard Communication Standard (29 CFR 1910.1200) in May 2024. The update brings the U.S. HCS into alignment with the United Nations’ Globally Harmonized System of Classification and Labelling of Chemicals, Revision 7 (GHS Rev. 7), with select provisions drawn from Revision 8. If you’re the person responsible for chemical safety at your facility, this affects your SDS library, your secondary container labels, your written Hazard Communication Program, and your worker training records — on a specific timeline that is already running.
This guide is written for facility managers, EHS leads, and procurement officers in manufacturing and industrial plants. It covers what changed, what the compliance dates mean for your operation specifically, and what to do in what order. You will not find a comprehensive legal analysis here. You will find the operational steps to avoid a citation.
Cross-reference this with the companion guide Reading an SDS: What Every Section Actually Means for deeper coverage of the new SDS section-level requirements.
What Changed: Plain-Language Summary of the May 2024 Final Rule
The 2024 final rule is not a complete overhaul. The 16-section SDS structure, the GHS pictograms, the label format — all of that carries over from the 2012 HCS. What changed is the classification criteria for specific hazard categories, certain label requirements, certain SDS content requirements, and a handful of definitions and procedural rules that matter operationally.
Hazard Classification Updates
Several hazard categories were reclassified or updated:
Aerosols. GHS Rev. 7 updated the aerosol classification system. Products that were classified as “aerosols” under the previous rule may now fall into more specific subcategories based on flammability and spray characteristics. If your facility uses any aerosol products, your suppliers may be reclassifying them. An aerosol lubricant that was previously labeled “flammable aerosol” may carry a different category and different precautionary statement under the updated criteria.
Desensitized explosives. A new hazard category added for materials that are explosive in their pure form but have been diluted or wetted to reduce that risk. Relevant primarily to chemical manufacturers, but shows up in SDS Section 2 for some industrial chemicals.
Combustible dust. This is the most operationally significant addition for manufacturing. GHS Rev. 7 formalizes combustible dust as a classifiable hazard. Under the 2024 rule, SDSs must now include combustible dust classification information in Section 2 (Hazard Identification) where applicable, with particle characteristics documented in Section 9 (Physical and Chemical Properties). Facilities that handle combustible dusts — wood dust, metal powders, sugar, grain, pharmaceutical powders, certain plastics — need to verify that their updated SDSs include this data when supplier-issued SDSs begin arriving under the new requirements.
Skin corrosion/irritation and serious eye damage/irritation. Updated subcategory criteria that may shift how some common cleaning and maintenance chemicals are classified. Practical effect: a product that was Category 2 skin irritant under the old criteria might move categories — changing which pictogram appears on the label and what precautionary statements are required.
Label Changes
Small packaging exemptions. The rule clarifies what label information can be omitted on very small containers (under 100 mL for some situations). If your facility uses sample-sized or small-volume chemical containers, the labeling exceptions now have cleaner regulatory language — but the default position remains full labeling unless a specific exception clearly applies.
Concentration ranges for trade secret cases. Suppliers who claim trade secret protection for ingredient concentrations can now use approved concentration ranges on the SDS rather than exact percentages, under specific documentation requirements. This changes what you may see in Section 3 (Composition) of updated SDSs for some formulated products. The ingredient will still be disclosed; only the precise concentration range may differ.
Released-for-shipment rule. The 2024 rule clarifies when a manufacturer or importer must have a label ready — specifically the “released for shipment” standard. This is primarily a manufacturer/importer compliance issue, but it affects the lead time you can expect for supplier label updates.
SDS Updates
New or updated information is required in several SDS sections under the revised rule:
- Section 2: Combustible dust classification where applicable; updated hazard statement codes and precautionary statements aligned with GHS Rev. 7
- Section 9: Particle size characteristics for solid materials, particularly relevant to powdered or granular products that pose combustible dust or inhalation hazards
- Section 3: Possible use of concentration ranges under trade secret provisions
Suppliers updating their formulations or SDSs to the new standard will issue new versions. Your SDS management system needs to be tracking version dates, not just product names.
The Compliance Dates: What They Mean for Your Operation
The phased timeline is the most important operational fact in this rule. Different deadlines apply to different actors in the supply chain, and the employer training and labeling deadlines are distinct from the manufacturer deadlines.
| Who | What | Deadline |
|---|---|---|
| Manufacturers/importers of substances | Updated labels and SDSs | January 19, 2026 |
| Distributors of substances | Ship only with updated labels | July 19, 2026 |
| Manufacturers/importers of mixtures | Updated labels and SDSs | July 19, 2027 |
| Distributors of mixtures | Ship only with updated labels | January 19, 2028 |
| Employers | Update workplace labels; train workers on new labels and SDSs | July 20, 2026 (substances) / July 19, 2028 (mixtures) |
A few operational notes on reading this table:
Most cleaning and maintenance chemicals are mixtures — formulated products containing multiple ingredients. That means the July 2027 / January 2028 dates apply to your suppliers. You should expect to see updated product labels and new SDS versions from your cleaning chemical suppliers primarily in 2026–2027 for substances and trailing into 2027–2028 for formulated cleaning products. But some suppliers will update early. Track version dates on every SDS.
The employer deadline is triggered by receipt of the updated labels, not by the supplier deadline. When your supplier ships you product with a new HCS 2024-compliant label, your clock for training and workplace label update starts. This is the part that catches facilities off guard: you receive an updated shipment, file the new SDS, and consider the job done. The training requirement has just been triggered.
What Your Facility Needs to Do — In Order
1. Audit Your Current SDS Library
Before the new labels start arriving, know what you have. OSHA’s general guidance (though not a hard rule in 1910.1200 itself) is that SDSs should be current — commonly interpreted as no older than 5 years. More critically: you need a system to track when new SDSs arrive so you know when a supplier has updated to the new standard.
Minimum audit items: - Total count of active chemicals in the SDS library - Date of current SDS for each product (found in Section 1 or the revision date at the bottom) - Identification of any SDS older than 5 years — flag for supplier outreach - Note which products are substances vs. mixtures (for tracking purposes against the deadline table above) - Identify any combustible-dust-relevant materials in your inventory: metal powders, wood dust, grain, sugar, certain plastics, pharmaceutical powders
If your SDS library is a binder in the break room, this is the time to move to a digital management system. Even a simple spreadsheet with product name, SDS date, revision date, and next-review date is better than no tracking. Several commercial SDS management platforms can auto-update SDSs from supplier databases — worth evaluating if your inventory is large.
2. Audit Secondary Container Labels
Secondary container labeling is where the gap between policy and reality usually lives. Walk your facility and look at:
- Dilution station output bottles
- Transfer containers and decant containers
- Spray bottles made up from concentrate
- Any container not in its original supplier packaging
Under 29 CFR 1910.1200(f)(6), secondary containers used only by the worker who filled them within the same shift don’t require a label (the “portable container exemption”). Any container that leaves the worker’s hand, gets used by others, or sits overnight requires a workplace label at minimum. The workplace label must include the product name and words, pictures, or symbols providing hazard information.
When your supplier’s new HCS 2024-compliant label arrives and your workplace labels were made from the old label, they no longer match. That’s not a citation by itself — but if you haven’t updated your secondary labels after training workers on the new content, you have a gap.
3. Update Your Written Hazard Communication Program
29 CFR 1910.1200(e) requires every employer to have a written Hazard Communication Program. The program must describe how you implement the HCS, including chemical inventory maintenance, labeling procedures, SDS access, and training. With the 2024 rule, the written program should be reviewed and updated to:
- Reference the current rule version and GHS revision alignment
- Describe how you track incoming SDS updates from suppliers
- Describe how secondary container labels are updated when supplier labels change
- Address combustible dust classification specifically, if applicable to your facility
- Identify your training trigger: what constitutes a “change” that requires refresher training under 1910.1200(h)
If your written program still references the 2012 HCS without noting the 2024 revision, update it. OSHA inspectors look at the written program and trace it to actual practice. A program that doesn’t reflect current requirements is an easy citation.
4. Plan Your Training Update
The HCS requires training at initial assignment and “whenever a new chemical hazard the employee has not previously been trained about is introduced into the work area” — and updated SDSs and labels constitute new information. The practical standard OSHA applies: when a label changes in a meaningful way (new pictogram, new signal word, new hazard statement), workers who use or work near that chemical need refresher training on what changed.
Training does not need to be a full-day classroom session. A 15-minute toolbox talk covering: “here’s the old label, here’s the new label, here’s what changed and what it means for how you handle this product” — documented with a sign-in sheet — satisfies the requirement for most chemical updates. What matters is: did you do it, did you document it, and does the documentation show which chemicals were covered.
Build your training calendar now. As supplier SDSs and labels roll in under the new rule, you’ll need a process for routing those updates to a training review, scheduling the refresher, and documenting it. A backlog of unaddressed label changes is a compliance liability.
5. Combustible Dust: Verify Your Exposures
The formal classification of combustible dust under GHS Rev. 7 gives OSHA a clearer enforcement path for SDS-level information. If your facility generates, handles, or stores materials that produce combustible dust, verify:
- Do your current SDSs for those materials classify combustible dust hazard in Section 2?
- Does Section 9 include particle characteristics (size, shape) where relevant?
- Does your written HazCom program address combustible dust as a classified hazard?
- Is your combustible dust hazard addressed in your NFPA 652 or applicable NFPA commodity-specific standard compliance documentation?
Note: NFPA 652 (Standard on the Fundamentals of Combustible Dust) requires a Dust Hazard Analysis (DHA) for facilities where combustible dust is present. The HCS update doesn’t create that requirement — it already existed — but the HCS classification update means your chemical communication documentation (SDS, labels, written program) should now explicitly name combustible dust where it exists, and your DHA and HazCom program should cross-reference each other.
Facilities most commonly affected: grain and food processing, wood products and furniture, metalworking (particularly aluminum, magnesium, titanium powders), pharmaceuticals, rubber/plastics compounding.
Procurement Considerations
When you’re sourcing cleaning and maintenance chemicals, the 2024 HCS update should show up in your vendor qualification process. Consider adding the following to RFP documentation and vendor compliance attestations:
SDS currency. Require that SDSs provided with products reflect the most current version from the manufacturer, with a revision date within the last 3 years. Reject products arriving with SDSs dated before the current year for known reformulations.
Supplier update notification. Request that suppliers notify you within 30 days when an SDS is updated due to regulatory changes, formula changes, or new hazard information. This is standard practice with established chemical distributors. Get it in writing in the supply agreement.
Combustible dust disclosure. For any solid or powder product, require explicit SDS disclosure whether combustible dust classification applies. “Not classified” is an acceptable answer — the absence of any answer is not.
HCS 2024 transition timeline. For substance-category products, suppliers should be able to commit to updated labels by January 19, 2026. For mixture products (most cleaning formulations), the deadline is July 19, 2027. Suppliers who cannot give you a timeline should be flagged.
Common Pitfalls
Assuming a new SDS filing = compliance complete. Receipt of an updated SDS triggers a training obligation. File the SDS and add the chemical to the training queue in the same step.
Secondary container labeling lagging by months. Production and maintenance staff fill spray bottles from updated-labeled concentrate containers and keep using old secondary labels for months. The fix is a label replacement protocol embedded in the secondary container process: when the concentrate label changes, all secondary labels for that product are reprinted within a defined period (10 working days is a reasonable standard).
Trade secret claims requiring updated documentation. If your facility or your suppliers use trade secret provisions for ingredient concentration ranges, the 2024 rule has updated the documentation requirements for those claims. Existing trade secret documentation may need to be refreshed. Don’t assume prior trade secret filings cover the new rule’s requirements without review.
Combustible dust facilities running outdated DHAs. The HCS update does not extend the deadline for your DHA — if it was overdue before, it’s still overdue. The HCS update just adds more regulatory surface area to an existing gap.
Waiting for OSHA to publish updated enforcement guidance before acting. OSHA enforcement on past HCS updates has generally been complaint-driven and inspection-triggered. “We’re waiting to see how enforcement goes” is not a compliance strategy.
HCS 2024 Compliance Audit Checklist
Use this to assess your current state and track progress. Complete one pass now and one pass 6 months before the substance deadline (January 2026).
HCS 2024 FACILITY COMPLIANCE AUDIT
Facility: ______________________ Date: ___________ Completed by: ___________
SDS LIBRARY
[ ] SDS inventory list current (all active chemicals documented)
[ ] All SDSs dated within 5 years or supplier notification pending
[ ] System in place to receive and log supplier SDS updates
[ ] Substances vs. mixtures identified in inventory (for deadline tracking)
[ ] Combustible-dust-relevant materials flagged and Section 2 classification verified
LABELING
[ ] Secondary container labeling procedure documented in written HazCom program
[ ] Walk-through of facility secondary containers completed — labels current
[ ] Protocol exists to update secondary labels when supplier labels change
[ ] Portable container exemption use documented (where applied)
WRITTEN HAZARD COMMUNICATION PROGRAM (29 CFR 1910.1200(e))
[ ] Program references 2024 HCS / GHS Rev. 7 alignment
[ ] SDS update tracking process described in writing
[ ] Secondary container label update process described
[ ] Combustible dust addressed (if applicable)
[ ] Training trigger criteria defined (what changes require refresher training)
TRAINING
[ ] Training records current for all current employees
[ ] Refresher training log tracks which chemicals were covered and when
[ ] Process to trigger training when new SDS/label arrives is defined and documented
PROCUREMENT
[ ] Vendor compliance attestation language references HCS 2024 update
[ ] Supplier update notification requirement in supply agreements
[ ] Combustible dust disclosure required for solid/powder products in RFPs
OVERALL STATUS
[ ] Substance deadline (Jan 19, 2026) — plan in place
[ ] Mixture deadline (Jul 19, 2027) — plan in place
[ ] Employer training deadline (Jul 20, 2026 / Jul 19, 2028) — plan in place
Run this checklist before a routine OSHA inspection, not during one.