One crew from Amersham and one crew from High Wycombe attended a report of a suspected gas leak.
Firefighters used two sets of breathing apparatus to enter the premises and carry out gas monitoring using specialist detection equipment, supported by a hose reel jet and a thermal imaging camera.
Following a thorough search, crews identified no hazardous readings within the building. The issue was traced to a carbon dioxide cylinder located in the cellar, which was isolated to remove the risk.