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Naughty or nice: where UL tests the safety of holiday products

UL holiday lights testing

December 15, 2015

With the holiday season in full swing, many people are outfitting their homes in festive décor, such as lighting strings, Christmas trees and more. However, these decorative items can pose safety risks, including fire and electrical shock hazards.

For this reason, UL has played an important role in developing and adapting holiday décor safety requirements for more than 90 years. In the late-1990s, UL updated its safety requirements for seasonal holiday and decorative products, resulting in a decrease in injuries and fatalities from related accidents.

While lighting strings have been around for nearly a century, not all lighting strings are created equal. That’s why UL tests products for indoor only versus indoor and outdoor use. A common test for indoor lights is a “pull test” — simulating common accidents like a person tripping over a wire and yanking the light strand from the socket. Outdoor lights undergo tests that evaluate how the product reacts to precipitation, extreme temperatures and water exposure.

Take a look at UL safety experts implementing these tests at the UL’s laboratory:

UL has been testing live Christmas trees for decades, evaluating the rates of heat between well-maintained, watered trees and poorly kept, dry trees. Intuitively, dry trees burn at a much faster rate, but watered trees are also at risk when they are too close to heat sources like fireplaces and candles.

See side-by-side testing of live Christmas trees in the video below:

As pre-lit artificial Christmas trees have increased in popularity, fire experts, both inside and outside of UL, have expressed the need for a certification program to address their risks. Scientific researchers found that pre-lit artificial Christmas trees are also a potential fire hazard, and some products carry a flashover risk due to their material make-up.

Manufacturers are striving to find the right balance between flame-retardant materials that may look less authentic, and materials that have a real-tree aesthetic but may be less flame-resistant.

For more information about how UL is helping people have a bright holiday season, visit: