VIDEO: Between an increase in cooking, keeping warm and the use of Holiday decorations, this turns into a busy time of year for firefighters, and if a fire breaks out in a home, every second matters. Firefighters are really stressing the importance of people keeping their bedroom doors closed at night. It's something they say more than half of people don't do. "That door is just a barrier to the smoke and the heat,” said Julie Popelka with the Cedar Rapids Fire Department. “Generally it's the smoke that will get people, and it's blocking the smoke that will get into your bedroom." Popelka says parents shouldn’t worry at night about their kids sleeping with the door closed.