A Perth mum remains in an induced coma, nine days after a charcoal heater mishap that has sparked a major health warning.
A man aged in his 50s and woman in her 40s were discovered unconscious and unresponsive inside a Westminster home by their teenaged children on June 25.
WATCH THE VIDEO ABOVE: Woman in induced coma after carbon monoxide poisoning emergency.
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They were taken to hospital having suffered carbon monoxide poisoning caused by charcoal that had been burning in an unvented bedroom at the property where the family had recently moved.
In a positive update, the father has been discharged from hospital.
But his wife remains in intensive care at Sir Charles Gairdner, more than a week after the incident.
Authorities have praised the quick thinking of the couple’s children, who sounded the alarm.
“It’s tragic but a testament to the actions of those children to alert the authorities and ventilate the home,” Department of Fire and Emergency Services (DFES) district officer John Manocchio said.
“When firefighters arrived with detectors they didn’t actually detect any carbon monoxide left in the house because it had been so well vented.”
Authorities say carbon monoxide poisoning is a growing danger inside homes this winter.
A family of four from Bunbury, 170km south of Perth, recently fell sick. They have now fully recovered after undergoing intensive therapy in hospital.
In western Sydney, four people were taken to hospital last week after a charcoal barbecue was used to heat a home.
Paramedics said they were called to a unit in Wentworthville after reports multiple people had fainted.
It was suspected they had suffered carbon monoxide poisoning.
Carbon monoxide poisoning symptoms include headaches, dizziness, nausea and confusion.
“It slowly builds up in the body, it impairs the body’s ability to release oxygen so the cells are starved of oxygen,” Sir Charles Gairdner Hospital clinical toxicologist Jason Armstrong told 7NEWS.
Armstrong’s advice if you find someone affected is to drag them outside as quickly as possible.
“Hopefully if it’s been a very brief exposure, people will recover fully and quickly,” Armstrong said.
“But if people have been badly poisoned or unconscious they may not ever recover consciousness.
“The priority is to get them to fresh air, get supplemental oxygen and get them to a medical facility as quickly as possible.”
DFES says charcoal fires are becoming more popular and cheaper to use outdoors but should never be used indoors where safety cannot be assured.