Christmas lights on decorations outside

Can You Leave Your Christmas Lights On Overnight? Experts Weigh In

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'Tis the season for snow, ornaments, cookies, and holiday cheer. It's also the season to decorate a beautiful tree and spend many nights gathered around it, gazing at the twinkling lights while drinking cocoa and reading your favorite Christmas stories. And the twinkling lights are one of my favorite parts of the season. I'm a professional when it comes to hanging lights and artfully weaving strands between the branches of a tree or on a house. But one thing I've never been clear on is can I leave my Christmas lights on overnight?

There are plenty of safety precautions you'll want to keep in mind while you're getting ready to hang your Christmas lights. Whether you're hanging lights on the tree, or hanging them outside, you'll want to test your lights before you hang them. You should check each strand of lights for frayed wires, broken bulbs, or loose connections before plugging them in, according to the Consumer Product Safety Commission (CPSC). Whether your strands are old or new, by making sure that your lights are safe before you plug them in you can avoid a lot of possible dangers. The CPSC went on to note that depending on whether or not you're talking about putting lights up outside or putting lights on the tree, the rules are a little different. For example, electric lights are a no-go if you're putting up a metallic tree this year, as faulty lights can charge your tree and electrocute anyone who touches it. Not exactly the kind of holiday excitement you're looking for.

Though the CPSC doesn't recommend leaving your Christmas lights on overnight, the television show MythBusters decided to take the question of whether or not leaving Christmas lights on your tree overnight can start a fire, and put it to the test. Jamie Hyneman and Adam Savage, the hosts of the show found out that every year in the United States, hundreds of holiday fires happen due to Christmas tree related causes, according to the National Fire Protection Association. In order to test whether or not leaving your Christmas lights on overnight can truly be hazardous (and cause a fire), Hyneman and Savage loaded up a freshly-cut tree with a reasonable five strands of Christmas lights, left it overnight, and came back to find a tree that was perfectly fine. But what about a tree that's not exactly fresh?


Next, the pair loaded an extremely dry tree up with five times the amount of lights they'd attempted the first time around. After just 40 minutes, the tree had heated up to 225 degrees. Though it wasn't enough to start a fire (and I doubt anyone's putting 25 strands of Christmas lights on their tree), it did show that Christmas lights alone aren't enough to light your tree on fire. In order for your Christmas tree lights to be a hazard, there has to be another factor, such as the number of strands, outlets, or wiring, that's causing the trouble. However, following the recommended guidelines of Christmas light safety is still a good idea. From being careful not to overload your outlets, to making sure your lighting cords aren't pinched or compromised, the Electrical Safety Foundation International has important guidelines for indoor holiday lighting projects that you should adhere to for the safest possible Christmas light experience.

Though there's a good chance you turn your lights off before bed, if you're like me, you may forget every once in a while. Consider investing in a Christmas light timer to make sure your lights are getting turned off at a reasonable hour every night. Not to mention putting your lights on a timer can make your electric bill much more manageable this holiday season, which is reason enough to be filled with Christmas cheer.

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