GHS hazard statement
H242: Heating may cause a fire
- H242
- Physical hazards
- Danger
H242 means “Heating may cause a fire”. It is a GHS hazard statement for Self-reactive substances and mixtures; Organic peroxides (Type C, D), shown with GHS02 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 C, D |  | Danger | Div 4.1, 5.2 Type C, D |
| Self-reactive substances and mixtures; Organic peroxides | Type E, F | | Warning | Div 4.1, 5.2 Type E, F |
What H242 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 H242
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+P378 | In case of fire: Use ... to extinguish. |
| 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 H242
No chemicals in our database are classified with H242 yet.
H242 frequently asked questions
What does H242 mean?
H242 means "Heating may cause a fire". It is a GHS hazard statement in the physical hazards group, covering Self-reactive substances and mixtures; Organic peroxides (Type C, D).
Which pictogram goes with H242?
H242 is shown with GHS02 (Flame). By category: Type C, D: GHS02, signal word Danger; Type E, F: GHS02, signal word Warning.
What signal word goes with H242?
It depends on the category: Type C, D: GHS02, signal word Danger; Type E, F: GHS02, signal word Warning.
Which precautionary statements go with H242?
The GHS data lists 11 precautionary statements for H242, 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)