H420 · Hazard statementHarms public health and the environment by destroying ozone in the upper atmosphere

Hazard statementEnvironmentalNot adopted: US, Canada, Mexico

H420 is the GHS hazard statement “Harms public health and the environment by destroying ozone in the upper atmosphere”. It is used for Hazardous to the ozone layer (chapter 4.2), Category 1. The English wording is the same as UN GHS Rev.11 in EU CLP. Not adopted in US OSHA, Canada and Mexico. The UN GHS Rev.11 label matrix lists 1 precautionary statement 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

Harms public health and the environment by destroying ozone in the upper atmosphere

UN GHS Rev.11, Annex 3, Table A3.1.3, PDF p. 307

US OSHA HCS

Not adopted

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

No matching OSHA hazard class or category (not adopted by OSHA).

EU CLP

Same as UN

EU_CLP_2025 · consolidated 1 Jul 2026

Harms public health and the environment by destroying ozone in the upper atmosphere

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

Canada (EN)

Not adopted

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

Environmental hazard classes are not adopted in the HPR.

Canada (FR)

Not adopted

WHMIS_2022 · SGH Rév.7, texte officiel

Environmental hazard classes are not adopted in the HPR.

Mexico (ES)

Not adopted

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

NOM-018-STPS-2015 covers physical and health hazards only (no environmental hazard statements).

Hazard classes and categories

Hazardous to the ozone layer (chapter 4.2) · Category 1

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

Pictogram: Exclamation mark (GHS07)

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.

Hazardous to the atmospheric system (chapter 4.2) (hazardous to the ozone layer), categories 1 (PDF p. 409)
P502

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.

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 H420. 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.