A coroner in New South Wales says more warnings are needed about the dangers of heated wheat bags, after a spate of house fires and the death of an elderly woman.
An inquest at Glebe Coroners Court in Sydney also resulted in a call for greater regulation of the personal warmers, which are heated in a microwave oven.
AAP reports there were 31 fires caused by wheat bags in NSW, injuring 11 people and killing one woman in the two years to December 2012.
Margaret Rae, 80, of Caringbah, died from smoke inhalation after a wheat bag in her bed ignited on 10 September, 2011.
Experts recommended a total ban on the bags on Tuesday during the inquest into Ms Rae's death and an inquiry into two fires started by wheat bags at Darling Point and Padstow.
Of the reported wheat-bag fires, 26 occurred while they were being microwaved.
Inspector Michael Gibson of the NSW Investigation and Fire Research Unit said hot spots could form unevenly in the bags if they were not heated properly.
Senior Constable Kelly Hall told the inquest she believed regular use of the wheat bag had dried out the grains, making them more likely to ignite when placed under bedding.
In handing down his findings, NSW Deputy Coroner Paul MacMahon said there was currently no national standard governing the bags and recommended Standards Australia develop one.
Therapeutic Goods Australia currently classes the bags as low risk. But Mr MacMahon said that classification was not necessarily accurate and should be revised to reflect the danger to the elderly and children.
AAP reports Mr MacMahon also recommended NSW Police and Emergency Services launch a public awareness campaign.