SMOKE detectors saved the lives of a woman and two children.
Two detectors went off after large candles on top of a storage heater melted.
The woman woke her two daughters, who are both under five, at their home at Grange Cottages in Marsden at 4.45am today.
They fled to safety unhurt.
Firefighters from Marsden and Slaithwaite took the heater off the wall, took it outside and cleared the smoke.
Sub-officer Mark Helliwell, of Slaithwaite, said: "The smoke alarms saved their lives.
"We could have been dealing with a far more serious incident."
"The woman thought the heater, which was in her bedroom, was off," said Sub-officer Helliwell. "But for some reason it came on and the candles were on top of it.
"The candles melted into the heater and gave off smoke in her bedroom. It also seeped into the children's bedroom below."