The warning, from Knottingley’s watch manager Noel Webster, comes after a house fire on Tuesday morning which was not detected by the owner’s dust-clogged smoke alarms.

The fire – caused by an unattended chip pan – was contained in the kitchen at the house on Grasmere Road, Knottingley, at about 6am.

The occupants – a mother and her teenage son – managed to get out of the house but were taken to hospital to be treated for smoke inhalation.

Mr Webster said: “They were very lucky. The kitchen door had been closed so the fire didn’t spread and had burned itself out by the time we arrived.

“The important message is to make sure smoke detectors are serviced properly. The detectors on this house had batteries in them and if you pressed the buttons on them they would have worked but they didn’t go off because of a back up of dust.

“People should vacuum their smoke detectors out at least every six months.”