GHS03
Flame over circle
Oxidiser: makes a fire burn hotter.
A black flame rising from a ring (a letter O), standing on a short horizontal bar.
- GHS code
- GHS03
- Name
- Flame over circle
- Signal word
- Danger or Warning, by category
- Old orange symbols (not one-to-one)
- O (Oxidising)
What it warns about
The flame over circle marks an oxidiser: a substance that gives off oxygen or otherwise makes other materials burn. It may not burn itself, but it can start a fire in something combustible such as wood, cloth or oil, or make an existing fire much fiercer. The circle is the O of oxygen and oxidiser, which is how to tell it apart from the plain flame.
The pictogram only names the kind of hazard; follow the product’s label and safety data sheet for how to use, store and dispose of it.
The hazard classes it stands for
EU and GB: CLP Regulation, Annex V
- Oxidising gases, category 1
- Oxidising liquids, categories 1, 2 and 3
- Oxidising solids, categories 1, 2 and 3
US: OSHA Hazard Communication Standard, Appendix C
- Oxidizers
A category number is the severity inside a class: category 1 (or type A) is the most severe. The hazard statements on the label (H-codes in the EU, such as H225 “Highly flammable liquid and vapour”) say exactly which class and category applies.
Signal word
Danger for oxidising gases and for oxidising liquids and solids of categories 1 and 2; Warning for category 3.
A label carries one signal word for the whole product: if any hazard calls for Danger, Warning does not appear as well.
Where you see it
At home
Pool shock and chlorine tablets based on calcium hypochlorite or trichloroisocyanuric acid, some concentrated hydrogen peroxide, potassium nitrate stump remover, and some ammonium-nitrate fertilisers.
At work
Medical and welding oxygen (with the gas cylinder), nitric acid, sodium chlorate and perchlorates, potassium permanganate, and concentrated hydrogen peroxide.
Examples of typical products, not a list of what any brand is classified as; the label on the product in your hand is what counts.
Where the rules differ
- OSHA and CLP list the same group (oxidising gases, liquids and solids) under this symbol.
- Under CLP, when the exploding bomb also applies, this pictogram becomes optional unless more than one of the fire pictograms is compulsory (Article 26(1)(a)).
- The yellow oxidizer label used in transport (49 CFR 172.426 in the US) shows a similar flame over a circle on a yellow background. It is a transport label, not the GHS pictogram.
The old orange symbol it replaced
Replaced the orange O (Oxidising) for oxidising gases, liquids and solids. It is not one-to-one: organic peroxides also carried O and now carry the flame, and Annex VII to CLP gives no direct translation for an O liquid or solid with R8, which has to be re-tested.
The mapping from the orange squares of Directive 67/548/EEC to the GHS pictograms is not one-to-one: CLP Annex VII translates each old classification separately, and some have no direct translation at all. All ten old symbols and what replaced them.
The other eight pictograms
- GHS01 exploding bomb: can explode, or react violently by itself
- GHS02 flame: catches fire easily
- GHS04 gas cylinder: gas held under pressure
- GHS05 corrosion: burns skin, damages eyes, eats metal
- GHS06 skull and crossbones: toxic or fatal in small amounts
- GHS07 exclamation mark: harmful or irritant: the milder health hazards
- GHS08 health hazard: serious or long-term harm to health
- GHS09 environment: toxic to fish and water life
Sources
- Regulation (EC) No 1272/2008 (CLP), Annex V: Hazard pictograms — UK National Archives copy (legislation.gov.uk) (Part 1, 1.3) — checked 2026-09-23
- 29 CFR 1910.1200, Hazard communication (OSHA Hazard Communication Standard), eCFR current text as amended to 13 February 2026 (Appendix C, Figure C.1) — checked 2026-09-23
- Regulation (EC) No 1272/2008 (CLP), Article 26: Principles of precedence for hazard pictograms — legislation.gov.uk (Article 26(1)(a)) — checked 2026-09-23
- Regulation (EC) No 1272/2008 (CLP), Annex VII: Translation table from classification under Directive 67/548/EEC — legislation.gov.uk (Table 1.1: O; R7, O; R8, O; R9) — checked 2026-09-23
- 49 CFR Part 172, Subpart E: Labeling (US hazardous materials transport labels), eCFR current text (§ 172.426) — checked 2026-09-23
Written in our own words from these official texts and checked on the date shown. The CLP text is the UK National Archives copy on legislation.gov.uk (EUR-Lex and unece.org did not answer a plain request from this host); it carries EU amendments made up to the end of 2020, and later EU changes may not be reflected. OSHA’s own pages refused the request, so the US text is the eCFR copy of the regulation.