GHS hazard statement
H240: Heating may cause an explosion
- H240
- Physical hazards
- Danger
H240 means “Heating may cause an explosion”. It is a GHS hazard statement for Self-reactive substances and mixtures; Organic peroxides (Type A), shown with GHS01 under the signal word “Danger”.
Hazard class and category
| Hazard class | Category | Pictogram | Signal word | UN transport class |
|---|---|---|---|---|
| Self-reactive substances and mixtures; Organic peroxides | Type A |  | Danger | Div 4.1, 5.2 Type A |
What H240 means
Self-reactive substances and mixtures are thermally unstable liquids or solids that can decompose strongly even without oxygen. Organic peroxides are organic substances containing the bivalent -O-O- structure that are also thermally unstable and may decompose, burn or react dangerously. Both are rated by type (A to G) depending on how violently they decompose.
The material can decompose with heat release, fire or explosion if it gets too warm, is contaminated, or is confined. Type A and B materials can explode or burn violently.
What to do
Keep at the temperature the supplier specifies, away from heat, sparks and flames, avoid contamination and friction or impact, keep in the original container, and store away from combustible and incompatible materials.
This is general guidance for the hazard class. The safety data sheet for your product always takes precedence.
Precautionary statements for H240
The GHS lists these precautionary statements for this hazard. Which ones appear on a label depends on the supplier's classification.
| Code | Statement |
|---|---|
| P210 | Keep away from heat, hot surface, sparks, open flames and other ignition sources. No smoking. |
| P234 | Keep only in original container. |
| P235 | Keep cool. |
| P240 | Ground/bond container and receiving equipment. |
| P280 | Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/... |
| P370+P372+P380+P373 | In case of fire: Explosion risk. Evacuate area. DO NOT fight fire when fire reaches explosives. |
| P403 | Store in a well-ventilated place. |
| P410 | Protect from sunlight. |
| P411 | Store at temperatures not exceeding ... °C/...°F. |
| P420 | Store separately. |
| P501 | Dispose of contents/container to ... |
Chemicals carrying H240
No chemicals in our database are classified with H240 yet.
H240 frequently asked questions
What does H240 mean?
H240 means "Heating may cause an explosion". It is a GHS hazard statement in the physical hazards group, covering Self-reactive substances and mixtures; Organic peroxides (Type A).
Which pictogram goes with H240?
H240 is shown with GHS01 (Exploding Bomb).
What signal word goes with H240?
The signal word for H240 is "Danger".
Which precautionary statements go with H240?
The GHS data lists 11 precautionary statements for H240, including P210, P234, P235, P240, P280. They cover prevention, response, storage and disposal. The full list is on this page.
Hazard statements describe the hazard of a classified substance or mixture. The classification of a specific product can differ, so use the supplier's SDS.
https://pubchem.ncbi.nlm.nih.gov/ghs/ghscode_10.txt (UN GHS Revision 10, retrieved 2026-10-12)