Because you cannot smell, see or taste carbon monoxide, it's very difficult to detect. The danger is that you can feel ill without realising the true cause. You may feel worse when your gas appliances are in use.

Symptoms of carbon monoxide poisoning are:

• Persistent headaches
• Dizziness
• Feeling sick and/or vomiting
• Confusion
• Extreme tiredness

If these symptoms occur, particularly while using a gas heating or hot water appliance, stop using the appliance immediately.

Ventilate your home by opening windows and doors and call the Emergency Service Provider 24-hour gas emergency line on 0800 111 999.

If necessary, contact your doctor and explain your symptoms and what you suspect.