H241 · Hazard statementHeating may cause a fire or explosion

Hazard statementPhysical

H241 is the GHS hazard statement “Heating may cause a fire or explosion”. It is used for Self-reactive substances and mixtures (chapter 2.8), Category Type B and Organic peroxides (chapter 2.15), Category Type B. The English wording is the same as UN GHS Rev.11 in US OSHA, EU CLP and Canada. Canada’s official French text is “Peut s’enflammer ou exploser sous l’effet de la chaleur” and Mexico’s Spanish text is “Puede incendiarse o explotar al calentarse”. The UN GHS Rev.11 label matrix lists 11 precautionary statements for it (UN only).

Maintained by Valenc. Data checked 2026-10-20.

Heading text: UN GHS Rev.11 Annex 3. Wording can differ by jurisdiction; see the table below.

Wording by jurisdiction

UN GHS Rev.11

Same as UN

GHS Rev.11 (2025), Annex 3

Heating may cause a fire or explosion

UN GHS Rev.11, Annex 3, Table A3.1.1, PDF p. 303

US OSHA HCS

Same as UN

HCS 2024 · primarily GHS Rev.7, some Rev.8

Heating may cause a fire or explosion

29 CFR 1910.1200 App. C, matched by wording

EU CLP

Same as UN

EU_CLP_2025 · consolidated 1 Jul 2026

Heating may cause a fire or explosion.

EU CLP (Reg. (EC) No 1272/2008), Annex III, Part 1

Canada (EN)

Same as UN

WHMIS_2022 · GHS Rev.7 (Rev.8 for chemicals under pressure)

Heating may cause a fire or explosion

GHS Rev.7 Annex 3 Table A3.1

Canada (FR)

Adopted

WHMIS_2022 · SGH Rév.7, texte officiel

Peut s’enflammer ou exploser sous l’effet de la chaleur

GHS Rev.7 Annex 3 Table A3.1

Mexico (ES)

Adopted

NOM-018-STPS-2015 · GHS 5th revised edition

Puede incendiarse o explotar al calentarse

Sustancias y mezclas que reaccionan espontáneamente, y peróxidos orgánicos · Tipo B

NOM-018-STPS-2015, DOF 9 October 2015, Apéndice C, Tabla C.1, PDF p. 30

Hazard classes and categories

Self-reactive substances and mixtures (chapter 2.8) · Category Type B
Organic peroxides (chapter 2.15) · Category Type B

UN GHS Rev.11 Annex 3, sections 1 and 2

FRMatières autoréactives (chapitre 2.8) ; et Peroxydes organiques (chapitre 2.15) · catégorie Type B

ESSustancias y mezclas que reaccionan espontáneamente, y peróxidos orgánicos · Tipo B (NOM-018-STPS-2015)

Pictograms: Exploding bomb (GHS01) for Self-reactive substances and mixtures, Type B; Organic peroxides, Type B · Flame (GHS02) for Self-reactive substances and mixtures, Type B; Organic peroxides, Type B

UN GHS Rev.11 Annex 3, section 3. Pictogram rules can differ by jurisdiction; see the GHS pictogram guide.

P statements in the UN GHS Rev.11 label matrix only

UN GHS Rev.11 only. EU CLP, US OSHA, Canada (GHS Rev.7) and Mexico assign different P statements; check the regulation for your market.

Self-reactive substances and mixtures (chapter 2.8), categories Type B (PDF p. 359)
P210 P234 P235 P240 P280 P403 P411 P420 P501 P370+P380+P375[+P378]
Organic peroxides (chapter 2.15), categories Type B (PDF p. 371)
P210 P234 P235 P240 P280 P403 P410 P411 P420 P501 P370+P380+P375[+P378]

UN GHS Rev.11 Annex 3, section 3. Each table covers the categories named; a P statement may apply to only some of them. Many apply only under conditions; check the conditions for use before putting them on a label.

Related codes

H240 H242

Change in UN GHS Rev.11

No change to the wording or the hazard classes in Annex 3 compared with Rev.10.

Sources

Each cell in the table names the official table and page for H241. Full citations, links and revision notes for UN GHS Rev.11, US OSHA, EU CLP, Canada and Mexico: Sources and revision notes.

These are regulatory phrases for labels and safety data sheets. Check them against the official source for your jurisdiction before use.