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Carbon monoxide

Key Points


  • Flammable gas
  • May react violently with other substances
  • In the event of a fire involving carbon monoxide, use fine water spray with normal fire-fighting clothing and breathing apparatus


  • Toxic when inhaled
  • Following short-term exposure symptoms such as headache, dizziness, confusion, disorientation, memory loss, fainting, coma and death may arise
  • Effects such as fast heart rate and breathing, low blood pressure and cardiac arrest may also occur
  • Long-term effects may occur such as behavioural changes
  • Long-term exposure to low concentrations of carbon monoxide may cause tiredness, headaches, sickness, dizziness, personality changes, memory problems, visual and hearing loss
  • Carbon monoxide may cause harm to the unborn child


  • Unlikely to pose a significant risk to the environment

Information on CO awareness and press releases on CO

All sections are available to download in PDF format.



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Compendium of Chemical Hazards