To learn more about safety phrases and to see a table of the safety phrases, please click here.
R-phrases consist of the letter R followed by a number, or a sequence of numbers. The precise meaning of each of these appears in the table below.
Single Risk Phrases (R-Phrases)
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.
R8:
Contact with combustible material may cause fire.
R9:
Explosive when mixed with combustible material.
R13 (Obsolete):
Extremely flammable liquid 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 flammable/explosive vapor-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.
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.
R35:
Causes severe burns.
R37:
Irritating to respiratory system.
R39:
Danger of very serious irreversible effects.
R40:
Possible risk of cancer.
R41:
Risk of serious damage to eyes.
R42:
May cause sensitization by inhalation.
R43:
May cause sensitization by skin contact.
R44:
Risk of explosion if heated under confinement.
R46:
May cause heritable genetic damage.
R47 (obsolete):
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.
R56:
Toxic to soil organisms.
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 breastfed babies.
R65:
Harmful: may cause lung damage if swallowed.
R66:
Repeated exposure may cause skin dryness or cracking.
R67:
Vapors may cause drowsiness and dizziness.
R68:
Possible risks of irreversible effects.
Combinations of R-Phrases
R14/15:
Reacts violently with water, liberating extremely flammable gases.
R15/29:
Contact with water liberates toxic, extremely flammable gas.
R20/21:
Harmful by inhalation and in contact with skin.
R21/22:
Harmful in contact with skin and if swallowed.
R20/22:
Harmful by inhalation and if swallowed.
R20/21/22:
Harmful by inhalation, in contact with skin and if swallowed.
R21/22:
Harmful in contact with skin and if swallowed.
R23/24:
Toxic by inhalation and in contact with skin.
R24/25:
Toxic in contact with skin and if swallowed.
R23/25:
Toxic by inhalation and if swallowed.
R23/24/25:
Toxic by inhalation, in contact with skin and if swallowed.
R24/25:
Toxic in contact with skin and if swallowed.
R26/27:
Very toxic by inhalation and in contact with skin.
R27/28:
Very toxic in contact with skin and if swallowed.
R26/28:
Very toxic by inhalation and if swallowed.
R26/27/28:
Very toxic by inhalation, in contact with skin and if swallowed.
R36/37:
Irritating to eyes and respiratory system.
R37/38:
Irritating to respiratory system and skin.
R36/38:
Irritating to eyes and skin.
R36/37/38:
Irritating to eyes, respiratory system and skin.
R39/23:
Toxic: danger of very serious irreversible effects through inhalation.
R39/24:
Toxic: danger of very serious irreversible effects in contact with skin.
R39/25:
Toxic: danger of very serious irreversible effects if swallowed.
R39/23/24:
Toxic: danger of very serious irreversible effects through inhalation and in contact with skin.
R39/23/25:
Toxic: danger of very serious irreversible effects through inhalation and if swallowed.
R39/24/25:
Toxic: danger of very serious irreversible effects in contact with skin and if swallowed.
Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed.
R39/26:
Very toxic: danger of very serious irreversible effects through inhalation.
R39/27:
Very toxic: danger of very serious irreversible effects in contact with skin.
R39/28:
Very toxic: danger of very serious irreversible effects if swallowed.
R39/26/27:
Very toxic: danger of very serious irreversible effects through inhalation and in contact with skin.
R39/26/28:
Very toxic: danger of very serious irreversible effects through inhalation and if swallowed.
R39/27/28:
Very toxic: danger of very serious irreversible effects in contact with skin and if swallowed.
Very toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed.
R42/43:
May cause sensitization by inhalation and skin contact.
R48/20:
Harmful: danger of serious damage to health by prolonged exposure through inhalation.
R48/21:
Harmful: danger of serious damage to health by prolonged exposure in contact with skin.
R48/22:
Harmful: danger of serious damage to health by prolonged exposure if swallowed.
Harmful: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin.
Harmful: danger of serious damage to health by prolonged exposure through inhalation and if swallowed.
Harmful: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed.
Harmful: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed.
R48/23:
Toxic: danger of serious damage to health by prolonged exposure through inhalation.
R48/24:
Toxic: danger of serious damage to health by prolonged exposure in contact with skin.
R48/25:
Toxic: danger of serious damage to health by prolonged exposure if swallowed.
Toxic: danger of serious damage to health by prolonged exposure through inhalation and in contact with skin.
Toxic: danger of serious damage to health by prolonged exposure through inhalation and if swallowed.
Toxic: danger of serious damage to health by prolonged exposure in contact with skin and if swallowed.
Toxic: danger of serious damage to health by prolonged exposure through inhalation, in contact with skin and if swallowed.
Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment.
R68/20:
Harmful: possible risk of irreversible effects through inhalation.
R68/21:
Harmful: possible risk of irreversible effects in contact with skin.
R68/22:
Harmful: possible risk of irreversible effects if swallowed.
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.
R68/21/22:
Harmful: possible risk of irreversible effects in contact with skin and if swallowed.
Harmful: possible risk of irreversible effects through inhalation, in contact with skin and if swallowed.
To contact MSDS Authoring Services regarding any additional questions about R-Phrases, click here.