[9] At the turn of the twentieth century, fire loss was on the rise in the United States, and the increasing use of electricity in homes and businesses posed a serious threat to property and human life.

[10] In order to determine and mitigate risk, Merrill proposed to open a laboratory where he would use scientific principles to test products for fire and electrical safety.

The Boston Board of Fire Underwriters turned this idea down, perhaps due to Merrill's youth and relative inexperience at the time.

With $350 of equipment, he opened a small laboratory on the third floor of a local fire insurance patrol station, signing UL's first test report on March 24, 1894.

[11] Merrill soon went to work on developing safety standards, conducting tests, and uncovering hazards.

[12] This work soon expanded, and throughout the twentieth century, UL certified many pivotal consumer technologies, such as vacuum cleaners, televisions, microwaves, personal computers, and more.

[14] In 1979, the organization moved its headquarters to a 153-acre campus in Northbrook, Illinois, 25 miles north of its former downtown Chicago location.