What's Behind the UL Mark?

Understand safety-certification ratings – and recognize the imposters.

When it comes to safety and health, we take a lot for granted. Few of us worry that the overload switch on a forgotten charging device will fail and allow the battery to catch fire. We assume an extension ladder will support us while we carry a pack of shingles to the roof. And who imagines that his grill will become an inferno while cooking a cheeseburger?

Yet product-related injuries continue to occur at alarming rates. Each year the Consumer Product Safety Commission (CPSC) tracks thousands of injuries and deaths involving everything from TV tip-overs to faulty pool drains. The organization initiates the voluntary recall of about 400 products every year. It recently recalled a child’s cabinet safety lock that kids could open, a crash-prone hydrostatic lawn tractor and a ceiling fan that posed fire and shock hazards.

As responsible consumers, we can improve our odds of avoiding accidents by checking products we consider purchasing for a safety-certification mark — the most well-known being that of Underwriters Laboratories (UL). “The UL mark means that product has been tested for safety and meets the applicable requirements for that product,” says John Drengenberg, UL’s director of consumer safety (and an electrical engineer). He points out that the mark is being used on more than just electrical and fire-resistant products, the traditional domains of UL. “For example, we have expanded into verification of environmental claims. We have learned that 95 percent of environmental claims have some irregularities associated with them — they are basically not true,” Drengenberg says.

“We have also gotten into life and health, including food and water,” he continues. “UL evaluates drinking water for 7,000 municipalities in the U.S. Our lab can test for 500 different contaminants.”

Drengenberg says that there are other reputable labs that write standards and certify product safety, including the Canadian Standards Association (CSA), but that UL is the biggest and best-known worldwide.

The certification process
Safety testing is generally voluntary, not federally mandated, although insurance companies and building codes may require the UL mark on certain products. However, retailers drive certification. “If a manufacturer brings a new power drill to the tool buyer for a home center,” says Drengenberg, “the first question will likely be whether it has been evaluated for safety by a third party. If not, the retailer will say, ‘Come back when it has.’”

In most cases, testing begins early in the process of tool development. “Under strict confidentiality, we look at specifications and samples that were pilot-built by the manufacturer,” says Drengenberg. “There is never an assurance the manufacturer will get the mark.”

The product is measured against established standards, or requirements, that were typically developed by UL engineers in collaboration with many people, including manufacturers, government agencies, safety experts, medical personnel and consumer advocates. Standards are constantly being revised and updated because of newly reported accidents or changes in technology. For example, the requirements for a toaster, an appliance that has been manufactured for generations, recently changed. Users’ inserting larger food items were causing toasters to jam and catch fire. Now a timer is required on all new models.

Although it’s often not necessary to test every component of a new tool because many (switches, electrical cords, wiring and circuit boards, etc.) have already been UL-certified, the organization still tests the complete tool. After testers gather information, they examine the product to be sure it meets established requirements and then perform tests as necessary. “Some requirements are not tests per se; they might be something very simple, such as measuring the thickness of the tool’s plastic enclosure or … whether a finger could manage to reach through a vent opening and touch a live part,” Drengenberg explains.

Other requirements — those for electrical, mechanical, fire and radiation safety — do involve testing. “For example, testing for operating temperatures is important because heat affects how long nearby components, such as insulation, last,” Drengenberg says. “This sort of testing is done for just about every component.” Input tests measure how much wattage an appliance draws because UL requires that a marking on the product show voltage, wattage or amperage. For a power drill, the requirements typically cover electrical, mechanical and fire safety. For a microwave oven, requirements also cover radiation.

With today’s battery-operated tools, there’s little worry about electrical shock because of the relatively low voltage, but there is concern about batteries, which can be prone to fires or explosions. “Because tools are very robust, we have not seen many [battery] problems. They are a little more common, however, in electronic devices such as laptop computers,” Drengenberg says.

When requirements are met, the manufacturer is authorized to put the UL mark on the product as it comes down the production line. But UL’s role doesn’t end there. Local inspectors can go into the factory at any time and pull a product off the line for testing.

False and misleading use
The UL mark is applied 22 billion times a year, with only a few counterfeits. As long as you shop at reputable retailers, you’re unlikely to be duped. UL anti-counterfeiting personnel work with the Department of Homeland Security to stop products with counterfeit labels from reaching the shelves.

The types of products most likely to bear counterfeit marks are typically high-volume, low-price items, such as extension cords, night-lights, Christmas lights, power strips and surge protectors. For products in the 35 or 40 categories where counterfeiting activity has been detected, UL has switched to a holographic mark that is very difficult to replicate.

If you ever see a product labeled “Tested for UL standard,” choose another model. “It is an out and out attempt to sell something that has not been certified by UL,” says Drengenberg. “They usually put UL in big letters. That’s advertising fakery.”

Although proper safety certification can guard against the dangers posed by shoddy manufacturing, it can only go so far to protect consumers. No matter what type of tool or appliance you’re using, it’s your responsibility to read instructions, be aware of potential hazards and take all necessary precautions to avoid accidents.

UL, initially known as the Underwriters’ Electrical Bureau, conducted its first test in 1894 on a noncombustible insulation material called “Mr. Shields.” Five years later, the organization had published 1,000 laboratory reports.