WORCESTER, Mass.

It only takes a minute for a crispy Christmas tree to touch off a raging inferno.

Researchers who set up a mock living room complete with curtains and an armchair — and then hit “record” as a tree-turned-torch engulfed the room in 63 seconds — hope their video will help people stay safe this holiday season.

“This has only been one minute since time of ignition and we’re seeing that the carpet has now ignited and that’s an indication of what we call flashover, where the room has gone from local burning at the tree to complete room involvement,” said Raymond Ranellone, director of the Fire Protection Engineering laboratory at Worcester Polytechnic Institute.

Engineers at the Massachusetts university used a freshly harvested Christmas tree that was left unwatered for three weeks in the room, recreating conditions that often occur after people decorate their homes for the holidays.

First, they touched the tree with a blowtorch. Instantly, the lower branches ignited. A few seconds later, flames were shooting out of the arms of the chair and thick smoke was billowing. It wasn’t long before the fake room was engulfed in a very real fireball.

Christmas trees were to blame for an average of 210 house fires annually between 2009 and 2013, according to the latest available data from the National Fire Protection Association. Those fires killed seven people, injured 19 others and caused $17.5 million in property damage, the organization says.

Experts say the risks can be minimized by following several simple steps.

“The best way to prevent a Christmas tree fire is to water it well every day, place it well away from heat sources, and dispose of it soon after the holiday,” said Massachusetts Fire Marshal Peter Ostroskey.

Since about one-third of tree fires are blamed on electrical problems, he said it’s always a good idea to turn off lights on the tree when leaving the house or going to bed.