Standards Guide

GHS Label Requirements

The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) — published by the United Nations and revised on a two-year cycle — defines how chemical hazards are classified and how those hazards must appear on container labels and safety data sheets. The United States implements it through OSHA's Hazard Communication Standard (29 CFR 1910.1200) and the European Union through the CLP Regulation (EC) No 1272/2008.

The Six Required Label Elements

A compliant supplier label for a hazardous chemical carries six elements. First, the product identifier — the name or number that matches section 1 of the safety data sheet. Second, the supplier identification: name, address, and telephone number. Third, the signal word — either "Danger" for more severe hazards or "Warning" for less severe ones, never both. Fourth, the hazard statements (H-codes), standardized sentences such as H225 "Highly flammable liquid and vapour." Fifth, the precautionary statements (P-codes) covering prevention, response, storage, and disposal. Sixth, the pictograms — red diamond frames with black symbols on white.

The wording of H and P statements is fixed by the classification, not composed by the labeler. That is the core design of GHS: two suppliers classifying the same substance the same way must produce the same core label in any implementing country.

The Nine Pictograms

Each pictogram is assigned by hazard class and category, and each has a reference page in our library:

• GHS01 Exploding bomb — explosives, self-reactives, organic peroxides
• GHS02 Flame — flammable liquids, gases, aerosols, pyrophorics, self-heating substances
• GHS03 Flame over circle — oxidizing gases, liquids, solids
• GHS04 Gas cylinder — gases under pressure
• GHS05 Corrosion — skin corrosion, serious eye damage, corrosive to metals
• GHS06 Skull and crossbones — acute toxicity categories 1–3
• GHS07 Exclamation mark — irritants, sensitizers, acute toxicity category 4
• GHS08 Health hazard — carcinogens, mutagens, reproductive and organ toxicity, aspiration
• GHS09 Environment — aquatic toxicity (mandatory in the EU, optional under OSHA)

Precedence Rules That Trip People Up

GHS prevents redundant or contradictory pictograms with precedence rules. If the skull and crossbones (GHS06) applies, the exclamation mark (GHS07) is not used for the same acute-toxicity hazard. If the corrosion pictogram (GHS05) applies for skin or eye effects, the exclamation mark is not used for skin or eye irritation. If the health hazard pictogram (GHS08) appears for respiratory sensitization, the exclamation mark is not used for skin sensitization or irritation. Signal words follow the same logic: a label never carries both "Danger" and "Warning" — the more severe classification wins.

US HazCom vs EU CLP: The Differences That Matter

The frameworks share the UN core but diverge at the edges. OSHA's HazCom 2012 originally aligned with GHS Revision 3; OSHA's May 2024 final rule updated the standard primarily to Revision 7, with compliance dates phased in from 2026 for substances and 2027 for mixtures. OSHA treats the environmental pictogram (GHS09) as outside its jurisdiction — it is permitted but not required in the US, while CLP requires it whenever aquatic toxicity classifications apply. The EU also maintains supplemental EUH statements (for example EUH208 for sensitizer traces) that have no US counterpart, and CLP prescribes minimum label and pictogram dimensions by package size, which OSHA does not.

For products sold into both markets, the practical approach is a single classification exercise against both rulebooks, one bilingual or multi-panel label, and separate SDS documents formatted for each jurisdiction — the 16-section SDS structure is shared, but required content details differ.

Workplace Containers and Small Packages

The full six-element label is a shipped-container requirement. For workplace containers — tanks, piping, secondary containers a worker fills for the shift — OSHA allows alternatives such as the full label, or a combination of product identifier with words, pictures, or symbols that convey the hazards, as long as the complete information is immediately available. Portable containers filled for immediate use by the person who fills them need no label at all. Small packages where the full label physically does not fit may use fold-out labels, tags, or reduced content following the practical accommodations both OSHA guidance and CLP Article 29 provide.

GHS Labels, Transport Placards, and the Fire Diamond

Three systems can legitimately appear on the same drum or building, and they do not conflict because they serve different readers. The GHS label informs the worker handling the container. Transport pictograms and placards under DOT and ADR rules inform carriers and responders during shipment — and where a transport pictogram for the same hazard is present on the outer packaging, the corresponding GHS pictogram may be omitted from that outer layer. The NFPA 704 diamond on buildings and tanks informs arriving fire crews about aggregate site risk. A common audit finding is treating one system as a substitute for another; each has its own trigger and its own required location.

Browse all nine pictogram reference pages in the GHS category, each with the official artwork, color specifications, and usage guidance.