UL stands for Underwriters Laboratories. For more than 100 years this organization has been developing safety standards, testing products for compliance and putting its mark on things we use every day. Now called UL, it’s one of the largest and best known safety certification organizations in the world.
UL is also an independent, third-party, non-profit organization. Meaning they have nothing to gain, therefore no stake in the products they test. Therefore their seal of approval is unbiased.
UL approval offers assurance that the safety and performance claims behind a product have been thoroughly verified by a third party. UL is also an accredited standards developer in the U.S. and Canada, setting industry standards for manufacturers that innovate new products. To date, UL has developed over 1,500 standards. There is also no such thing as general UL approval, instead they break up their certification into being listed, recognized, or classified.