Fire rescue services responded to a medical call early Wednesday morning and found all five people sick and confused on the front steps of a home.
Capt. Carol Messenger, public information officer with Vancouver Fire, says crews managed to shut down the residential gas service to the home.
She says they also searched for any other possible causes for the generation of carbon monoxide and then ventilated the home.
The fire department is reminding people that carbon monoxide alarms should be installed in every level of a home because the gas has no odour, is poisonous and can be deadly.