Modifications to a cooker could have prevented a tragic accident in which two people were killed by carbon monoxide poisoning.

An inquest into the deaths of Zocika O’Kelly, 53 and David Roots, 55 - who were discovered dead on Christmas Day 2008 in the home they shared at 21 Belgrave Street, Eccles - revealed the couple were killed after a gas cooker in their kitchen was left on.

The inquest at County Hall today revealed the top oven door of the Belling G755 cooker had been closed at some point prior to their death, releasing fatal amounts of carbon monoxide into the home.

While the cooker was not found to be in breach of manufacturing standards, the same model was said to have been involved in three other such deaths nationwide.

The design of the cooker, which is made in Turkey by manufacturers Glen Dimplex, has since been modified to prevent such accidents and modifications are currently being carried out to those cookers already installed.

The British Standards Institution have also proposed an amendment to the current safety standard which calls for appliances to be tested while being used "contrary to manufacturers’ instructions."

David Roots’ wife, Patricia, said she believed manufacturers must have known of the dangers connected before the deaths, but she welcomed the news that action was being taken.

She said: "I’m very angry that something like that is allowed to be manufactured and put in a person’s home.

"Some people can’t read instructions - any child could go into a kitchen and close the grill."

And she added: "It’s a bit like shutting the door after the horse has gone - it’s too late for us but perhaps not too late for others."