Risk Phrases

Chemical data sheets available in many countries now contain codes for certain "risk phrases", shown as R23, R45 etc. These risk phrase codes have the following meanings:

• R1 Explosive when dry.
• R2 Risk of explosion by shock, friction, fire or other source 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.
• R13 Extremely flammable liquefied gas
• R14 Reacts violently with water.
• R15 Contact with water liberates extremely flammable gases.
• R16 Explosive when mixed with oxidizing substances.
• R17 Spontaneously flammable in air.
• R18 In use, may form inflammable/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 acid 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 the eyes.
• R42 May cause sensitization by inhalation.
• R43 May cause sensitization by skin contact.
• R44 Risk of explosion if heated under confinement.
• R45 May cause cancer.
• R46 May cause heritable genetic damage.
• R47 May cause birth defects
• 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 to the ozone layer.
• R60 May impair fertility.
• R61 May cause harm to the unborn child.
• R62 Risk of impaired fertility.
• R63 Possible risk of harm to the unborn child.
• R64 May cause harm to breastfed 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.

It is current safety policy at Oxford University that a written COSHH assessment must be provided when a substance to be used has been assigned any of the risk phrases R42, R43, R45, R46, R48, R49, R60 or R61. Other hazards may also dictate the preparation of a suitable COSHH assessment.