GHS REFERENCE / H-CODES
GHS hazard statements (H-codes)
The "what can go wrong" half of every SDS and label. Each code below links to its own page: official text, hazard class and category, signal word, pictogram, the precautionary statements paired with it, and real substances that carry it — all from the same tables our classification engine writes into SDS Section 2.
Physical hazards (H2xx)
| Code | Statement | Class · category | Signal | |
|---|---|---|---|---|
| H224 | Extremely flammable liquid and vapor. | Flammable liquids · Category 1 | Danger |  |
| H225 | Highly flammable liquid and vapor. | Flammable liquids · Category 2 | Danger | |
| H226 | Flammable liquid and vapor. | Flammable liquids · Category 3 | Warning | |
| H227 | Combustible liquid. | Flammable liquids · Category 4 | Warning | |
| H271 | May cause fire or explosion; strong oxidizer. | Oxidizing liquids and solids · Category 1 | Danger |  |
| H272 | May intensify fire; oxidizer. | Oxidizing liquids and solids · Categories 2 and 3 | Danger (Category 2) / Warning (Category 3) | |
| H290 | May be corrosive to metals. | Corrosive to metals · Category 1 | Warning |  |
Health hazards (H3xx)
| Code | Statement | Class · category | Signal | |
|---|---|---|---|---|
| H300 | Fatal if swallowed. | Acute toxicity, oral · Categories 1 and 2 | Danger |  |
| H301 | Toxic if swallowed. | Acute toxicity, oral · Category 3 | Danger | |
| H302 | Harmful if swallowed. | Acute toxicity, oral · Category 4 | Warning |  |
| H303 | May be harmful if swallowed. | Acute toxicity, oral · Category 5 | Warning | |
| H304 | May be fatal if swallowed and enters airways. | Aspiration hazard · Category 1 | Danger |  |
| H310 | Fatal in contact with skin. | Acute toxicity, dermal · Categories 1 and 2 | Danger | |
| H311 | Toxic in contact with skin. | Acute toxicity, dermal · Category 3 | Danger | |
| H312 | Harmful in contact with skin. | Acute toxicity, dermal · Category 4 | Warning | |
| H313 | May be harmful in contact with skin. | Acute toxicity, dermal · Category 5 | Warning | |
| H314 | Causes severe skin burns and eye damage. | Skin corrosion · Category 1 (1A, 1B, 1C) | Danger | |
| H315 | Causes skin irritation. | Skin irritation · Category 2 | Warning | |
| H316 | Causes mild skin irritation. | Skin irritation · Category 3 (mild irritation) | Warning | |
| H317 | May cause an allergic skin reaction. | Skin sensitization · Category 1 (1A, 1B) | Warning | |
| H318 | Causes serious eye damage. | Serious eye damage · Category 1 | Danger | |
| H319 | Causes serious eye irritation. | Serious eye irritation · Category 2A | Warning | |
| H320 | Causes eye irritation. | Eye irritation · Category 2B | Warning | |
| H330 | Fatal if inhaled. | Acute toxicity, inhalation · Categories 1 and 2 | Danger | |
| H331 | Toxic if inhaled. | Acute toxicity, inhalation · Category 3 | Danger | |
| H332 | Harmful if inhaled. | Acute toxicity, inhalation · Category 4 | Warning | |
| H333 | May be harmful if inhaled. | Acute toxicity, inhalation · Category 5 | Warning | |
| H334 | May cause allergy or asthma symptoms or breathing difficulties if inhaled. | Respiratory sensitization · Category 1 (1A, 1B) | Danger | |
| H335 | May cause respiratory irritation. | Specific target organ toxicity, single exposure · Category 3 (respiratory tract irritation) | Warning | |
| H336 | May cause drowsiness or dizziness. | Specific target organ toxicity, single exposure · Category 3 (narcotic effects) | Warning | |
| H340 | May cause genetic defects. | Germ cell mutagenicity · Category 1 (1A, 1B) | Danger | |
| H341 | Suspected of causing genetic defects. | Germ cell mutagenicity · Category 2 | Warning | |
| H350 | May cause cancer. | Carcinogenicity · Category 1 (1A, 1B) | Danger | |
| H351 | Suspected of causing cancer. | Carcinogenicity · Category 2 | Warning | |
| H360 | May damage fertility or the unborn child. | Reproductive toxicity · Category 1 (1A, 1B) | Danger | |
| H361 | Suspected of damaging fertility or the unborn child. | Reproductive toxicity · Category 2 | Warning | |
| H370 | Causes damage to organs. | Specific target organ toxicity, single exposure · Category 1 | Danger | |
| H371 | May cause damage to organs. | Specific target organ toxicity, single exposure · Category 2 | Warning | |
| H372 | Causes damage to organs through prolonged or repeated exposure. | Specific target organ toxicity, repeated exposure · Category 1 | Danger | |
| H373 | May cause damage to organs through prolonged or repeated exposure. | Specific target organ toxicity, repeated exposure · Category 2 | Warning | |
Environmental hazards (H4xx)
Environmental classes appear on SDSs and labels; in the US they sit with EPA and DOT rather than OSHA.
| Code | Statement | Class · category | Signal | |
|---|---|---|---|---|
| H400 | Very toxic to aquatic life. | Hazardous to the aquatic environment — acute · Category 1 | Warning |  |
| H401 | Toxic to aquatic life. | Hazardous to the aquatic environment — acute · Category 2 | No signal word | |
| H402 | Harmful to aquatic life. | Hazardous to the aquatic environment — acute · Category 3 | No signal word | |
| H410 | Very toxic to aquatic life with long lasting effects. | Hazardous to the aquatic environment — chronic · Category 1 | Warning | |
| H411 | Toxic to aquatic life with long lasting effects. | Hazardous to the aquatic environment — chronic · Category 2 | No signal word | |
| H412 | Harmful to aquatic life with long lasting effects. | Hazardous to the aquatic environment — chronic · Category 3 | No signal word | |
| H413 | May cause long lasting harmful effects to aquatic life. | Hazardous to the aquatic environment — chronic · Category 4 | No signal word |
Reference information, not legal or professional advice. Statement texts and allocations follow GHS Rev 9 / 29 CFR 1910.1200 Appendix C as implemented by our classification engine; the regulatory text and agency practice control. Claims last reviewed July 23, 2026.
The engine writes these for you.
When SDS HQ authors an SDS or a container label, it assigns the hazard statements, signal word, pictograms, and precautionary statements from these same tables — automatically, with the calculation shown.