(Harrisburg) -- With a cold snap expected this weekend, fire safety advocates are reminding people to use extra care if they’re using alternative heating sources. Firefighters say they worry every winter, as some people turn to space heaters to try to save money on their heating bills. Don Konkle of the Pennsylvania Fire and Emergency Services Institute says improper use of space heaters can easily result in a fire. "People aren't going to allow their families to freeze to death. They'll use about any means they can to stay warm. We understand that and aren't saying you shouldn't do that. We're just simply saying you should follow the instructions, you should respect the fact that they aren't as safe as a central heating thing," Konkle says. Statistics back up Konkle's point. A National Fire Prevention Association report from 2009 shows space heaters accounted for a third of home-heating-related fires and four out of five home-heating-related deaths. Konkle says space heaters should be treated like candles -- kept away from anything flammable and turned off when no one is in the room with them.  Although no definitive cause could be determined -- space heaters were suspected in the fire that claimed the lives of seven children in Perry County last March - and the blaze that killed four children and a woman in Harrisburg in October, 20-10.