Emergency services were called to a suspected carbon monoxide leak at a house in Lanteglos yesterday evening.
At 7.30pm a fire crew from Polruan scrambled to the end of terrace house in Whitecross after a carbon monoxide detector sounded.
A representative from Cornwall Fire and Rescue Service said when the firefighters arrived they recorded a carbon monoxide reading of zero
The occupants of the house were checked over by paramedics at the scene.
A representative from South West Ambulance Service said: “A rapid response vehicle and two ambulance crews attended.
“A number of patients were treated at the scene.”