SASKATOON -- The Saskatoon Fire Department urges homeowners to invest in carbon monoxide detectors after a family of nine was sent to hospital for carbon monoxide poisoning.

Assistant Fire Chief Wayne Rodger said carbon monoxide is a product of combustion and a problem with an appliance could lead to the gas building up in a home.

"The early signs are flu-like symptoms, there's nausea with onset of vomiting, that ill-feeling, and that develops into headaches and that can, with higher exposures, lead to unconsciousness and it could lead to death," he said.

On Wednesday at 9:19 a.m., emergency crews responded to a home in the 300 block of Avenue T North for reports of multiple family members inside feeling ill and a carbon monoxide alarm sounding.

Rodger said five adults and four children were showing signs of carbon monoxide poisoning.

Upon arrival, Rodger said first responders found one person unconscious.

Firefighters discovered carbon monoxide levels of over 100 parts-per-million at the front entrance. While they searched for others in the home, crews made additional readings of 160 PPM and 190 PPM.

SaskEnergy crews remained on scene for a few hours after the family was taken to hospital.

Rodger said SaskEnergy shut down the home's furnace and hot water tank and recommend they be checked by a licensed contractor.