Two years on, how many of us have a CO (carbon monoxide) detector in our homes or one near our beds that we check regularly?

Very few, according to the parents of the dead children Bobby and Christi Shepherd

Their mother Sharon Wood and her husband Paul have said: "Lives are still being lost to carbon monoxide and we believe the majority of the population is still not fully aware of the causes or symptoms of this type of gas poisoning.

"We had very limited knowledge of carbon monoxide before we lost our precious children."

The Wakefield couple, along with the children's father Neil Shepherd and his partner Ruth Beatson – who were on holiday with them when the tragedy happened – launched a new schools' poster competition this week at the House of Lords with the support of Ed Balls, Secretary of State for Children, Schools and Families.

"I believe raising awareness through the poster campaign is a fantastic step in the right direction," said Mr Shepherd.

"If my children had been aware of the dangers and symptoms of carbon monoxide, they might have put the thought into my head and maybe, just maybe, they would be here today."

Stephanie Trotter, of charity CO-Gas Safety, which has organised the competition, said: "It's a good way to get to parents through their children.

"Children are brilliant at soaking up information."

CO-Gas Safety compiles its own data and estimates that on average carbon monoxide poisoning kills 40 people a year in the UK and injures around 300, but the true figures are likely to be much higher because carbon monoxide poisoning often is not tested for by doctors or gas engineers.

"We've been campaigning for 13 years and still can't get the Gas Emergency Service to test for it.

"If you call them out all they can do is turn off your supply," says Miss Trotter.

"GPs rarely test for CO either, or they say come back next week when the nurse is here and that's too late.

"Or they offer to do an arterial blood test which is painful and puts people off.

"It's incredibly difficult to prove."

WHAT IS CARBON MONOXIDE POISONING?
It is produced when carbon-based fuels, including gas, oil, wood and coal, do not burn fully because of a lack of oxygen supply.

You can't see it, taste it or smell it but it can kill quickly and without warning.

When CO enters the body, it prevents the blood from bringing oxygen to cells, tissues and organs. This lack of oxygen causes the body tissues and cells to die.

HOW TO STOP IT HAPPENING
Ensure that gas appliances and/or flues are installed correctly and serviced regularly by a CORGI-registered engineer.
If you have appliances that use other fossil fuels, make sure they are serviced and maintained by a competent person who is registered with Hetas for solid fuel, Oftec for oil.
Always make sure there is enough fresh air in the room containing your gas appliance.
Ensure chimneys and flues are not blocked up and that vents are not covered.
Get your chimney swept from top to bottom once a year by a qualified sweep.
Never use ovens or gas ranges to heat your home.

CHECK FOR

• Yellow or orange rather than blue flames (apart from fuel effect fires or flueless appliances, which display this colour flame).


• Soot or yellow/brown staining around or on appliances.


• Pilot lights that frequently blow out.


• Increased condensation inside windows.

SYMPTOMS TO LOOK OUT FOR

• Tiredness


• Drowsiness


• Headaches


• Giddiness


• Nausea


• Vomiting


• Chest pains


• Breathlessness


• Stomach pains


• Erratic behaviour or confusion


• Visual problems

WHAT TO DO

• Stop using all cooking and heating appliances


• Open all the doors and windows


• Call the National Gas Emergency Service Helpline on 0800 111999


• Go to the nearest A&E department immediately

FIT AN ALARM
The best way to ensure your home is carbon monoxide-free is to install a European-approved alarm that works just like a smoke alarm and makes a loud noise if carbon monoxide is detected.

Comment

Should all homes have carbon monoxide detectors fitted? Vote now in our poll on the right.