Flame

The hazard classes it stands for

EU and GB: CLP Regulation, Annex V

• Flammable gases, categories 1A and 1B
• Aerosols, categories 1 and 2
• Flammable liquids, categories 1, 2 and 3
• Flammable solids, categories 1 and 2
• Self-reactive substances and mixtures, Types B, C, D, E and F
• Pyrophoric liquids and pyrophoric solids, category 1
• Self-heating substances and mixtures, categories 1 and 2
• Substances and mixtures which, in contact with water, emit flammable gases, categories 1, 2 and 3
• Organic peroxides, Types B, C, D, E and F
• Desensitised explosives, categories 1, 2, 3 and 4

US: OSHA Hazard Communication Standard, Appendix C

• Flammables
• Self-reactives
• Pyrophorics
• Self-heating
• Emits flammable gas
• Organic peroxides
• Desensitized explosives

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 or Warning, depending on the category. Danger goes with the most flammable categories (for example flammable liquids of categories 1 and 2, flash point below 23 °C); Warning goes with flammable liquids of category 3 (flash point 23 to 60 °C), aerosols of category 2 and the milder categories of the other classes.

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

Aerosol sprays such as hairspray, deodorant, spray paint and polish; lighter fluid and barbecue lighter gel; methylated spirits; acetone nail-polish remover; white spirit; alcohol hand gel; petrol in a can.

At work

Paint thinners and solvents, adhesives and contact cement, fuel, propane and butane (with the gas cylinder), laboratory alcohols, and the resin hardeners that are organic peroxides.

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 has a fourth category of flammable liquid (flash point above 60 °C and up to 93 °C) that takes the signal word Warning but no pictogram; CLP stops at category 3 (flash point up to 60 °C). So a US label can say Warning with no flame on a liquid that is not classified as flammable in the EU.
• CLP gives flammable gases of category 2 and aerosols of category 3 no pictogram at all (Annex V, 1.6).
• Under CLP, when the flame applies, the gas cylinder becomes optional (Article 26(1)(e)).
• The red flammable liquid and flammable gas labels on packages in transport (49 CFR 172.417 and 172.419 in the US) are transport labels, not the GHS pictogram, even though they show a flame too.

The old orange symbol it replaced

Replaced the orange F (Highly flammable) and F+ (Extremely flammable). It also took over organic peroxides, which used to carry the O (Oxidising) square. The mapping is not one-to-one: Annex VII to CLP says an F or F+ liquid has to be re-sorted by its flash point and boiling point, and an F+ gas can end up in category 2, with no pictogram.

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
• GHS03 flame over circle: oxidiser: makes a fire burn hotter
• 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