The woman, named locally as Diane Hill and thought to be in her forties, suffered 40% burns after the petrol caught fire in the kitchen of her home in York last night, firefighters said.
She was attempting to decant the fuel from one container to another using a jug.
It comes two days after Cabinet Office minister Francis Maude told Sky News that people should avoid petrol shortages by putting extra fuel in a jerrycan in the garage.
Sky's North of England correspondent Gerard Tubb, in York, said: "Ms Hill was tipping petrol from a plastic petrol container for which she did not have a spout into the jug because her daughter, in her late teens or early twenties, needed petrol for her car.
"The vapour from the petrol in the open-topped jug was ignited by the gas cooker which was on.
After Ms Hill's daughter raised the alarm, paramedics and firefighters arrived at the house within minutes. Ms Hill was subsequently taken to hospital. Read More