A Reading coroner has called for the boiler safety classification system to be changed after a faulty boiler caused the death of a woman in Berkshire.

Katie Haines, 31, was found lying in the bath by her husband after he returned from work in February 2010. The inquest, which was held earlier this month, heard that their boiler had previously been certified as "at risk" amid concerns over the ventilation system. Both Mrs Haines and her pet cat died as a result of carbon monoxide poisoning.

Berkshire coroner Peter Bedford recorded a narrative verdict and said he planned to recommend changes to the "at risk" category. He said that if there was any problem with any gas appliance, it should be condemned outright.

The couple had arranged for a British Gas engineer to visit their home to make repairs to the boiler, but the tradesman cancelled the appointment and they had been "too busy to reschedule".

Mr Haines said the seriousness of having the boiler classified as "at risk" had not been stressed to them clearly enough, and they had not realised the danger they were in.

Mr Haines told the coroner: "The irony is the smoke alarm broke and we got a smoke alarm that came in a packet with a carbon monoxide detector without us realising. We didn't even unpack it. We could have just turned it on. We didn't realise the importance of it."