blog

Chemical Hazard Identification and Labeling: A Practical Guide to OSHA HazCom and GHS

Written by Safety Sign | Sep 23, 2026, 3:15:00 PM

How to read, apply, and stay compliant with chemical hazard labels in the workplace

In the United States, OSHA's Hazard Communication Standard (29 CFR 1910.1200) governs chemical hazard identification and labeling and aligns with the Globally Harmonized System (GHS). Every shipped chemical container must carry a label with six required elements, and workplaces must keep a Safety Data Sheet (SDS) for each hazardous chemical. A 2024 update to the standard is now phasing in, with the first major compliance date on May 19, 2026.

Chemical hazard communication is one of the most frequently cited areas in workplace safety inspections, and for good reasons: a clear, correct label is often the last line of defense between a worker and an exposure. This guide explains what the rules require, what each part of a chemical label means, and what recent changes you should plan for. It is written for facility and safety managers who need practical answers, not legal boilerplate.

What is the OSHA Hazard Communication Standard?

The Hazard Communication Standard (HazCom or HCS), codified at 29 CFR 1910.1200, is OSHA's rule requiring employers to evaluate and communicate the hazards of chemicals they produce or import to employees. Since 2012, it has been aligned with the United Nations' Globally Harmonized System of Classification and Labeling of Chemicals (GHS), which standardizes label formats and Safety Data Sheets across countries. The standard rests on three pillars: consistent chemical labels, standardized 16-section SDSs, and worker training.

What are the six required elements of a GHS label?

Every label on a shipped hazardous-chemical container must include these six elements:

  • Product identifier: the chemical name or code that matches the SDS.
  • Signal word: either “Danger” or “Warning.”
  • Hazard statement(s): standardized phrases describing the nature of the hazard (for example, “Causes serious eye damage”).
  • Pictogram(s): the red-bordered diamond symbols that convey hazards at a glance.
  • Precautionary statement(s): recommended measures for handling, storage, and first aid.
  • Supplier information: the name, address, and phone number of the manufacturer or importer.

You can see all six elements laid out on OSHA's Labels and Pictograms guide (OSHA 3636). For ready-to-apply labels, Safety Sign's GHS labels and broader chemical hazard labels collections cover pictogram, chemical-name, and custom formats.

What do the GHS pictograms mean?

GHS defines nine pictograms. Eight are used under OSHA HazCom for physical and health hazards; the ninth (Environment) is used internationally but is not mandatory on OSHA-regulated shipped labels. The nine are:

  • Health Hazard: carcinogens, respiratory sensitizers, reproductive and target-organ toxicity.
  • Flame: flammables, pyrophorics, self-heating and self-reactive chemicals.
  • Exclamation Mark: irritants, skin sensitizers, and less-severe acute toxicity.
  • Gas Cylinder: gases stored under pressure.
  • Corrosion: skin burns, serious eye damage, and materials corrosive to metals.
  • Exploding Bomb: explosives, self-reactives, and organic peroxides.
  • Flame Over Circle: oxidizers.
  • Skull and Crossbones: substances with severe acute toxicity.
  • Environment: aquatic toxicity (used globally; not required by OSHA).

OSHA's pictogram QuickCard shows each symbol. Individual GHS pictogram signs are useful for posting at storage areas and process points.

Danger vs. Warning: what is the difference?

Only one signal word appears on a label. Per OSHA's HazCom FAQ, “Danger” is used for the more severe hazards and “Warning” for the less severe ones. The signal word is assigned by hazard class and category, so it is not a judgment call; it follows the classification of the chemical.

What changed in the 2024 HazCom update, and when are the deadlines?

OSHA published a final rule updating HazCom on May 20, 2024, which took effect July 19, 2024. It maintains alignment with GHS (primarily Revision 7, with select Revision 8 elements) and adds provisions such as labeling for small containers and rules for chemicals “released for shipment.” Details are on OSHA's HazCom rulemaking page. (Note: These OSHA compliance dates were current at the time of publishing and are subject to change. Verify the latest details at osha.gov before acting.)

Compliance is phased in. OSHA confirms that the first deadline, for manufacturers, importers, and distributors to update labels and SDSs for substances, was extended from January 19, 2026 to May 19, 2026, and states that all other compliance dates are extended by four months as well. That means the later milestones (workplace labels, program, and training for employers, and the separate deadlines for mixtures) each shift four months past their originally published dates. Because only the May 19, 2026 date is stated verbatim by OSHA, confirm the exact dates that apply to your operation on the compliance-date extension notice. During the transition, you may comply with the previous standard, the updated standard, or both. (Note: These OSHA compliance dates were current at the time of publishing and are subject to change. Verify the latest details at osha.gov before acting.)

How should you label workplace (secondary) containers?

When you transfer a chemical into a secondary container, OSHA gives you two options: reproduce the full GHS label, or use the product identifier plus words, pictures, or symbols that convey at least general hazard information. A container filled for the immediate use of the employee who transferred it does not require a label. Pre-printed secondary container labels make this straightforward and consistent across a facility.

Where do NFPA 704 and HMIS fit in?

The NFPA 704 “fire diamond” and the HMIS color-bar system are voluntary in-plant systems that OSHA permits for workplace labeling, as long as they do not conflict with the required hazard information and workers are trained to read them. One point causes real confusion: in NFPA and HMIS a higher number (up to 4) means a greater hazard, while in GHS a lower category number (1) means a greater hazard. NFPA and HMIS do not replace GHS shipped-container labels or SDSs. Safety Sign offers NFPA signs and labels and custom HMIS signs for facilities that use these systems.

What about Safety Data Sheets and right-to-know postings?

Every hazardous chemical needs an SDS in the standardized 16-section format, and employers must keep SDSs readily accessible to employees in their work area during each shift (paper or electronic both qualify). A visible right-to-know information sign at the SDS station helps employees (and inspectors) find the information quickly. Dedicated chemical storage signs round out a compliant storage area.

Frequently asked questions

Does OSHA require all nine GHS pictograms? No. Eight cover physical and health hazards used under HazCom; the Environment pictogram is used internationally but is not required on OSHA-regulated shipped labels.

Do I need to relabel older stock right now? During the transition period you may follow the previous or the updated standard. Plan updates around the phased deadlines beginning May 19, 2026 for substances. (Note: These OSHA compliance dates were current at the time of publishing and are subject to change. Verify the latest details at osha.gov before acting.)

Is an electronic SDS binder acceptable? Yes, provided employees have reliable, barrier-free access during every shift, with a backup for outages.

Sources

OSHA: Hazard Communication Standard, 29 CFR 1910.1200

OSHA: HazCom 2024 rulemaking and compliance-date extension notice

OSHA: HazCom FAQ (signal words, secondary containers)

OSHA 3636: Labels and Pictograms; OSHA 3491: Pictogram QuickCard

OSHA 3514: Safety Data Sheet QuickCard (16 sections)