Five fire crews rushed to a Long Crendon industrial building after people smelt burning inside.
Emergency services were alerted to the incident in Drakes Drive at 3.30pm yesterday (Thursday).
When the crews, two from Aylesbury, one from Princes Risborough, one from Thame and one from Wheatley, arrived they traced the smell to a lightfitting and isolated the electricity.
One woman at the scene had to be treated for the effects of breathing in smoke.