P378 · Precautionary statementUse ... to extinguish.

Precautionary · ResponsePhysical

P378 is the GHS precautionary statement “Use ... to extinguish”. UN GHS Annex 3 assigns it to 10 hazard classes. The English wording is the same as UN GHS Rev.11 in EU CLP and Canada. OSHA uses it only inside combined statements. Canada’s official French text is “Utiliser… pour l'extinction” and Mexico’s Spanish text is “Utilizar... para la extinción”.

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

Use ... to extinguish.

UN GHS Rev.11, Annex 3, Table A3.2.3, PDF p. 327

US OSHA HCS

In combined statements

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

Used in OSHA App. C only inside combined statements: P370+P378, P370+P380+P375[+P378]. Precautionary statements may be combined (App. C, C.2.4.6).

EU CLP

Same as UN

EU_CLP_2025 · consolidated 1 Jul 2026

Use… to extinguish.

EU CLP, Annex IV, Part 2

Canada (EN)

Same as UN

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

Use ... to extinguish.

GHS Rev.7 Annex 3 Table A3.2

Canada (FR)

Adopted

WHMIS_2022 · SGH Rév.7, texte officiel

Utiliser… pour l'extinction.

GHS Rev.7 Annex 3 Table A3.2

Mexico (ES)

Adopted

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

Utilizar... para la extinción

NOM-018-STPS-2015, DOF 9 October 2015, Apéndice D, Tabla D.1, PDF p. 37

Hazard classes and categories

Chemicals under pressure (chapter 2.3) · Category 1, 2
Flammable liquids (chapter 2.6) · Category 1, 2, 3, 4
Flammable solids (chapter 2.7) · Category 1, 2
Self-reactive substances and mixtures (chapter 2.8) · Category Types B, C, D, E, F
Pyrophoric liquids (chapter 2.9) · Category 1
Pyrophoric solids (chapter 2.10) · Category 1
Substances and mixtures which, in contact with water, emit flammable gases (chapter 2.12) · Category 1, 2, 3
Oxidizing liquids (chapter 2.13) · Category 1, 2, 3
Oxidizing solids (chapter 2.14) · Category 1, 2, 3
Organic peroxides (chapter 2.15) · Category Types B, C, D, E, F

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

Conditions for use

if water increases risk. ... Manufacturer/supplier or the competent authority to specify appropriate media.

Quoted as published in UN GHS Rev.11 Annex 3, section 2. List markers are shown as bullets.

Related codes

P370+P378 P370+P380+P375[+P378]

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 P378. 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.