GHS Pictograms Explained: What Each of the 9 Means

There are nine GHS hazard pictograms. Each is a red-bordered diamond (a square set on one of its points) containing a black symbol on a white background, and each one signals a family of hazards — flammable, corrosive, toxic, and so on. They are defined by the CLP Regulation, the GB and EU implementation of the UN's Globally Harmonized System of Classification and Labelling of Chemicals (GHS), and on any safety data sheet they are your first clue to what a substance can do to people and property.

What are the GHS hazard pictograms?

A GHS hazard pictogram is a standardised warning symbol used on chemical labels and safety data sheets. Under CLP each supply pictogram is a red diamond frame with a black hazard symbol on a white centre, and there are nine of them in total. They replaced the older orange-square European symbols (such as the black "X" irritant and cross-and-bones designs) when CLP fully applied to mixtures. CLP became mandatory for mixtures on 1 June 2015.

A pictogram never appears alone. On a compliant label and in Section 2 of a safety data sheet it sits alongside a signal word — either "Danger" (more severe) or "Warning" (less severe) — and one or more hazard statements (H-codes, e.g. "H314 Causes severe skin burns and eye damage"). The picture tells you the hazard category family; the signal word and H-statements tell you the severity and specifics.

What does each GHS pictogram mean?

The table below summarises all nine. The final column flags why the symbol matters when you build a COSHH assessment — covered in more detail further down.

Pictogram	Code	What it warns about	Relevance to health risk
Exploding bomb	GHS01	Explosives, self-reactive substances, organic peroxides	Physical hazard (fire/explosion)
Flame	GHS02	Flammable gases, aerosols, liquids and solids; pyrophoric, self-heating and water-reactive substances	Physical hazard (fire)
Flame over circle	GHS03	Oxidising gases, liquids and solids (intensify fire)	Physical hazard (fire)
Gas cylinder	GHS04	Gases under pressure (compressed, liquefied, refrigerated, dissolved)	Physical hazard
Corrosion	GHS05	Skin corrosion, serious eye damage, and corrosive to metals	Health hazard (skin/eye)
Skull and crossbones	GHS06	Acute toxicity (severe) — can be fatal or toxic in small amounts	Health hazard (acute)
Exclamation mark	GHS07	Acute toxicity (harmful), skin/eye irritation, skin sensitisation, respiratory irritation, narcotic effects; also harmful to the ozone layer	Health hazard (lower severity)
Health hazard (starburst figure)	GHS08	Carcinogenicity, mutagenicity, reproductive toxicity, respiratory sensitisation, target-organ toxicity, aspiration hazard	Health hazard (serious/chronic)
Environment (dead tree and fish)	GHS09	Hazardous to the aquatic environment	Environmental, not a health hazard

It helps to group the nine into three families:

• Physical-hazard symbols — the exploding bomb, flame, flame-over-circle and gas cylinder (GHS01–GHS04). These warn about fire, explosion and pressure.
• Health-hazard symbols — corrosion, skull and crossbones, exclamation mark and the starburst figure (GHS05–GHS08). These warn about harm to the body, from an immediate acid burn to a long-latency cancer risk.
• The environmental symbol — GHS09, which flags aquatic toxicity.

The two most often confused are the exclamation mark (GHS07) and the health-hazard figure (GHS08). The exclamation mark covers lower-severity, generally shorter-term effects: irritation, mild acute toxicity and sensitisation. The starburst figure is reserved for the serious, often chronic effects — carcinogens, mutagens, reproductive toxicants, respiratory sensitisers and aspiration hazards. If you see the figure with the white starburst on its chest, treat the substance as one that can cause lasting harm.

Which pictograms actually matter for a COSHH assessment?

This is where the pictograms earn their keep — and where a lot of generic guidance stops short. The Control of Substances Hazardous to Health Regulations 2002 (COSHH) deal with risks to health, not with fire, explosion or environmental damage. So the pictograms do not map one-to-one onto a COSHH assessment.

• The health-hazard symbols (GHS05–GHS08) are the ones that directly drive a COSHH assessment: corrosion, acute toxicity, irritation/sensitisation and the serious chronic hazards.
• The physical-hazard symbols (GHS01–GHS04) — bomb, flame, flame-over-circle and gas cylinder — point mainly to a different regime: the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR). A flammable solvent can, of course, also be harmful to breathe, in which case it carries a health pictogram too.
• The environment symbol (GHS09) is generally outside COSHH altogether; aquatic-hazard controls sit under environmental legislation.

It's also worth knowing what COSHH does not cover even where health is involved: asbestos, lead and radioactive substances each have their own dedicated regulations rather than falling under COSHH. This is general guidance, not a definitive ruling on any specific substance — always work from the classification on the actual product's safety data sheet.

Where do pictograms appear on a safety data sheet — and why aren't they enough?

A safety data sheet follows a standard 16-section structure, and the pictograms live in Section 2, Hazard identification, together with the signal word and the full list of H- and P-statements.

Here's the practical catch: a pictogram alone can't populate a COSHH assessment. The corrosion symbol appears whether a substance causes reversible irritation or permanent, irreversible skin destruction — you only know which from the H-statement and signal word. To assess risk properly you also need the exposure route, the tasks involved, quantities and frequency, existing controls, and any workplace exposure limit (HSE publishes these in EH40). The picture starts the conversation; Sections 2, 8 and 11 of the SDS finish it.

This is precisely the gap that turns a quick label-glance into hours of transcription. Safe Foundry reads the classification data out of each SDS and drafts a structured COSHH assessment from it — you can see the full flow on our how it works page, and what's captured from Section 2 on the features page. If you'd rather just look up what a symbol or statement means, our help centre has short reference notes.

Do GHS pictograms tell you how dangerous a substance is?

No — not on their own. A pictogram indicates the kind of hazard, not the degree. Severity is communicated by two other elements on the label:

• The signal word: "Danger" for the more severe hazard categories, "Warning" for the less severe.
• The hazard statement: the H-code and its wording pin down the exact classification and category.

Two products can carry the identical corrosion diamond yet differ enormously in how quickly and how badly they injure skin. Reading the signal word and H-statement — not just counting the symbols — is what makes a hazard judgement defensible.

How do CLP pictograms differ from transport (ADR) labels?

They are separate systems and easy to confuse. CLP supply pictograms (the nine described here) go on the packaging a worker handles and on the safety data sheet. Transport labels, governed by the carriage-of-dangerous-goods rules (ADR and related regulations), are the diamond placards on drums, IBCs and vehicles, and they use their own class numbers and colours. There is visual overlap — a flame appears in both — but a substance's transport class is not the same thing as its CLP hazard class, and you should read each in its own context.

The practical bottom line

The nine GHS pictograms are a fast, universal shorthand for "what could this chemical do?" — but they are the headline, not the article. For a COSHH assessment, focus first on the health-hazard symbols, then read the signal word and H-statements that sit beside them, and remember that fire and environmental hazards are governed by other regulations. Get into the habit of reading Section 2 as a whole, and the pictograms become a reliable first filter rather than a false sense of certainty.