Two children were treated for smoke inhalation at a house in Sandiacre after a candle caused curtains to set alight on Halloween.
The incident happened at 6.40pm on October 31 during fire fighter strikes and was the first blaze attended to by reserve crews.
A spokesman for Derbyshire Fire and Rescue Service said: “A Halloween party went horribly wrong when a candle set fire to the curtains inside the property. Two 13-year-old children were treated at the scene for smoke inhalation.”
Reserve crews attended a total 56 incidents in Derbyshire since the start of the four-day industrial action at, with a total of 149 calls being received by 999 control room operators.
Assistant chief fire officer Gavin Tomlinson said: “Some simple fire safety precautions could have prevented all of these fires.
“Candle safety and not cooking after consuming alcohol, are just two common causes of fire that as a service we try to raise awareness of and prevent. Thankfully no one was injured, but next time it could be a different story.
“I would encourage everyone to stay vigilant and be aware that fire can happen to anyone.”