Emergency advice

Carbon monoxide poisoning:

  1. Call 999.
  2. Move the casualty into fresh air.
  3. Encourage the casualty to breathe normally.
  4. Monitor the casualty until help arrives.

What is carbon monoxide and carbon monoxide poisoning?

Carbon monoxide is a poisonous gas that’s hard to detect as it has no taste or smell. If someone breathes in carbon monoxide in large quantities, for example from smoke or vehicle exhaust fumes, it can prove fatal.

Carbon monoxide gas may come from:

  • exhaust fumes of motor vehicles in a confined space.
  • smoke from incomplete burning of coal, gas, logs and oil in a confined space.
  • blocked chimney flues.
  • disposable or portable barbeques in a confined space.
  • emissions from defective gas or paraffin heaters or boilers.

Signs and symptoms

When exposed to low levels, people may have:

  • headache.
  • confusion or inappropriate behaviour.
  • aggression.
  • flushed skin.
  • nausea and vomiting.

When exposed to high levels, they may have:

  • cherry-red or grey-blue skin colouration.
  • difficulty in breathing.
  • reduced level of response leading to unresponsiveness.

What to do

  1. Call 999 or 112 for emergency help.

    • Tell the ambulance you suspect fume inhalation.
  2. Help to move the casualty from the source of the fumes into fresh air.

    • Do not enter the fume-filled area yourself.
  3. Support the casualty and encourage them to breathe normally.

  4. Stay with the casualty until help arrives.

    • Monitor and record the casualty’s vital signs – breathing, pulse and level of response.
  5. If the casualty is found unresponsive open the airway, check their breathing and prepare to treat for an unresponsive casualty.

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Related first aid advice

How to do the primary survey

Use the primary survey to quickly assess the situation and check the casualty for injuries or conditions that could be immediately life threatening. Find out what to do.

How to put an adult in the recovery position

It’s safe to place someone in the recovery position who is not responding to you but is breathing normally. Learn what to do.

How to do CPR on an adult

If an adult is unresponsive and not breathing normally, you need to call 999 or 112 for emergency help and start CPR straight away. Learn what to do.

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