Firies warn of carbon monoxide poisoning

The head of NSW Fire & Rescue says people need to talk about the danger of carbon monoxide poisoning, as an elderly woman recovers after bringing an outdoor heater inside.

A neighbour found the 84-year-old woman in her Surry Hills unit on Thursday night and called emergency crews.

Fire & Rescue Superintendent Tom Cooper said the elderly lady put herself in grave danger.

"We urge people to have a conversation about the dangers of carbon monoxide poisoning."

There's been a spate of incidents this month, and this week firefighters issued an urgent warning about the lethal danger posed by using outdoor heaters inside.

In the past two weeks alone, 13 people have required hospital treatment after burning such things indoors, according to the NSW Poisons Information Centre.

Meanwhile, a 43-year-old man has suffered burns to 18 per cent of his body after trying to refill a heater with ethanol during a birthday celebration in Turramurra.

Ambulance crews were called to Terrigal Avenue just after 1am on Friday and treated five people.

The 43-year-old and a 39-year-old have been taken to Royal North Shore Hospital.

Fire investigators are looking into the cause of the heater explosion.