R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations. The list was consolidated and republished in Directive 2001/59/EC, where translations into other EU languages may be found.

These risk phrases are used internationally, not just in Europe, and there is an ongoing effort towards complete international harmonization.

R1 Explosive when dry

R2 Risk of explosion by shock, friction, fire or other sources of ignition

R3 Extreme risk of explosion by shock, friction, fire or other sources of ignition

 

R4 Forms very sensitive explosive metallic compounds

R5 Heating may cause an explosion

 

R6 Explosive with or without contact with air

 

R7 May cause fire

 

R8 Contact with combustible material may cause fire

 

R9 Explosive when mixed with combustible material

 

R10 Flammable

 

R11 Highly flammable

 

R12 Extremely flammable

 

R14 Reacts violently with water

 

R15 Contact with water liberates extremely flammable gases

 

R16 Explosive when mixed with oxidising substances

 

R17 Spontaneously flammable in air

 

R18 In use, may form flammable/explosive vapour-air mixture

 

R19 May form explosive peroxides

 

R20 Harmful by inhalation

 

R21 Harmful in contact with skin

 

R22 Harmful if swallowed

 

R23 Toxic by inhalation

 

R24 Toxic in contact with skin

 

R25 Toxic if swallowed

 

R26 Very toxic by inhalation

 

R27 Very toxic in contact with skin

 

R28 Very toxic if swallowed

 

R29 Contact with water liberates toxic gas.

 

R30 Can become highly flammable in use

 

R31 Contact with acids liberates toxic gas

 

R32 Contact with acids liberates very toxic gas

 

R33 Danger of cumulative effects

 

R34 Causes burns

 

R35 Causes severe burns

 

R36 Irritating to eyes

 

R37 Irritating to respiratory system

 

R38 Irritating to skin

 

R39 Danger of very serious irreversible effects

 

R40 Limited evidence of a carcinogenic effect

 

R41 Risk of serious damage to eyes

 

R42 May cause sensitisation by inhalation

 

R43 May cause sensitisation by skin contact

 

R44 Risk of explosion if heated under confinement

 

R45 May cause cancer

 

R46 May cause heritable genetic damage

 

R48 Danger of serious damage to health by prolonged exposure

 

R49 May cause cancer by inhalation

 

R50 Very toxic to aquatic organisms

 

R51 Toxic to aquatic organisms

 

R52 Harmful to aquatic organisms

 

R53 May cause long-term adverse effects in the aquatic environment

 

R54 Toxic to flora

 

R55 Toxic to fauna

 

R56 Toxic to soil organisms

 

R57 Toxic to bees

 

R58 May cause long-term adverse effects in the environment

 

R59 Dangerous for the ozone layer

 

R60 May impair fertility

 

R61 May cause harm to the unborn child

 

R62 Possible risk of impaired fertility

 

R63 Possible risk of harm to the unborn child

 

R64 May cause harm to breast-fed babies

 

R65 Harmful: may cause lung damage if swallowed

 

R66 Repeated exposure may cause skin dryness or cracking

 

R67 Vapours may cause drowsiness and dizziness

 

R68 Possible risk of irreversible effects

 

Combinations:

R14/15 Reacts violently with water, liberating extremely flammable gases

R15/29 Contact with water liberates toxic, extremely flammable gases

R14/15/29 Reacts violently with water, liberating toxic, extremely flammable gases

R20/21 Harmful by inhalation and in contact with skin

R20/21/22 Harmful by inhalation, in contact with skin and if swallowed

R20/22 Harmful by inhalation and if swallowed

R21/22 Harmful in contact with skin and if swallowed

R23/24 Toxic by inhalation and in contact with skin

R23/25 Toxic by inhalation and if swallowed

R24/25 Toxic in contact with skin and if swallowed

R26/27 Very toxic by inhalation and in contact with skin

R26/28 Very toxic by inhalation and if swallowed

R26/27/28 Very toxic by inhalation, in contact with skin and if swallowed

R27/28 Very toxic in contact with skin and if swallowed

R36/38 Irritating to eyes and skin

R36/37/38 Irritating to eyes, respiratory system and skin

R37/38 Irritating to respiratory system and skin

R39/24 Toxic: danger of very serious irreversible effects in contact with skin

R39/23/24 Toxic: danger of very serious irreversible effects through inhalation and in contact with skin

R39/24/25 Toxic: danger of very serious irreversible effects in contact with skin and if swallowed

R39/26Very Toxic: danger of very serious irreversible effects through inhalation

R39/28Very Toxic: danger of very serious irreversible effects if swallowed

R39/26/28 Very Toxic: danger of very serious irreversible effects through inhalation and if swallowed

R39/26/27/28 Very Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed

R45/46 May cause cancer and heritable genetic damage

R48/21 Harmful: danger of serious damage to health by prolonged exposure in contact with skin

R48/20/21 Harmful: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin

R48/20/22 Harmful: danger of serious damage to health by prolonged exposure through inhalation and if swallowed

R48/20/21/22 Harmful: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed

R48/21/22 Harmful: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed

R48/23 Toxic: danger of serious damage to health by prolonged exposure through inhalation

R48/23/24 Toxic: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin

R48/24 Toxic: danger of serious damage to health by prolonged exposure in contact with skin

R48/24/25 Toxic: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed

R48/25 Toxic: danger of serious damage to health by prolonged exposure if swallowed

R48/23/25 Toxic: danger of serious damage to health by prolonged exposure through inhalation and if swallowed

R48/23/24/25 Toxic: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed

R51/53 Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment

R68/20 Harmful: possible risk of irreversible effects through inhalation

R68/20/21 Harmful: possible risk of irreversible effects through inhalation and in contact with skin

R68/20/22 Harmful: possible risk of irreversible effects through inhalation and if swallowed

R68/21 Harmful: possible risk of irreversible effects in contact with skin

R68/21/22 Harmful: possible risk of irreversible effects in contact with skin and if swallowed

R68/22 Harmful: possible risk of irreversible effects if swallowed

R68/20/21/22 Harmful: possible risk of irreversible effects through inhalation, in contact with skin and if swallowed