Gas safety
Suspect carbon monoxide when several people feel unwell
Leave for fresh air as soon as it is safe and call 999 for suspected exposure. Do not re-enter to locate the source or retrieve belongings.
Last reviewed: 2026-09-20
Why it matters
Carbon monoxide has no warning smell; several people becoming ill together may signal exposure.
Wrong action
Ruling out poisoning because nobody smells gas.
Correct action
Leave for fresh air as soon as it is safe and call 999 for suspected exposure.
What to do
- Notice shared headache, dizziness or nausea while fuel-burning equipment is operating.
- Leave for fresh air as soon as it is safe and call 999 for suspected exposure.
- Do not re-enter to locate the source or retrieve belongings.
If something happens
For serious injury, unconsciousness or difficulty breathing, keep yourself safe, call 999 and follow the operator.
Sources and review
- Department of Health, Centre for Health Protection — CHP: carbon monoxide poisoning
Last reviewed: 2026-09-20
This page provides general home-safety information and does not replace medical, legal, electrical, or other professional advice.