The UL enterprise is a global safety science company headquartered in
Northbrook, Illinois, composed of three organizations, UL Research Institutes, UL Standards & Engagement and UL Solutions.
Established in 1894, the UL enterprise was founded as the Underwriters' Electrical Bureau (a bureau of the
National Board of Fire Underwriters),
and was known throughout the 20th century as Underwriters Laboratories. On January 1, 2012, Underwriters Laboratories became the parent company of a for-profit company in the U.S named UL LLC, a
limited liability corporation
A limited liability company (LLC for short) is the US-specific form of a private limited company. It is a business structure that can combine the pass-through taxation of a partnership or sole proprietorship with the limited liability o ...
, which took over the
product testing and certification business. On June 26, 2022, the companies rebranded into three distinct organizations that make up the UL enterprise.
UL Solutions partners with customers and stakeholders in more than 100 countries to help solve safety, security and sustainability challenges and is also responsible for managing and issuing the highly respected portfolio of UL Marks. The company is one of several companies approved to perform safety testing by the U.S. federal agency
Occupational Safety and Health Administration
The Occupational Safety and Health Administration'' (OSHA ) is a large regulatory agency of the United States Department of Labor that originally had federal visitorial powers to inspect and examine workplaces. Congress established the agenc ...
(OSHA).
OSHA maintains a list of approved testing laboratories, which are known as
Nationally Recognized Testing Laboratories.
According to Lifehacker, UL Solutions is the best known product safety and certification organization globally.
History

Underwriters Laboratories Inc. was founded in 1894 by William Henry Merrill Jr. After graduating from the
Massachusetts Institute of Technology
The Massachusetts Institute of Technology (MIT) is a Private university, private Land-grant university, land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern t ...
(MIT) with a degree in
electrical engineering in 1889, Merrill went to work as an electrical inspector for the Boston Board of Fire Underwriters. 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.
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, however, perhaps due to Merrill's youth and relative inexperience at the time.
In May 1893, Merrill moved to Chicago to work for the Chicago Fire Underwriters' Association. His task was to inspect the city's fire alarm systems. He was also sent to the 1893 World's Fair to inspect the Fair's electrical installations and the Palace of Electricity. In order to determine and mitigate risk in his role as an electrical inspector, Merrill found it necessary to conduct tests on building materials and electrical components. Upon seeing a growing potential in this field, Merrill stayed in Chicago to found Underwriters Laboratories. He received initial funding from the Chicago Fire Underwriters' Association and the Western Union, a local insurance organization. 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.
Merrill soon went to work on developing safety standards, conducting tests, and uncovering hazards. In the early years, UL tested three main types of products: devices meant to stop fire (such as fire extinguishers), devices meant to resist fire (such as fire doors), and devices that frequently caused fire (like wires used for electrical installations). 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.
UL published its first standard, "Tin Clad Fire Doors", in 1903. In 1906, UL established a Label Service for certain product categories that require more frequent inspections. Products that passed UL's testing and regular inspections were given a UL label, which eventually evolved into the UL Mark. From 1905 to 1979, UL Headquarters was located at 207-231 East Ohio Street in Chicago. In 1979, the organization moved its headquarters to a 153-acre campus in Northbrook, Illinois, 25 miles north of its former downtown Chicago location.
UL Solutions has evolved from its roots in electrical and fire safety to address broader safety issues, such as hazardous substances, water quality, food safety, performance testing, safety and compliance education, and environmental sustainability.
On January 1, 2012, Underwriters Laboratories became the parent company of a for-profit company in the U.S named UL LLC, a limited liability corporation. The for-profit company took over the product testing and certification business.

In 2022, the company revised their go-to-market strategy to include three separate organizations - UL Solutions, UL Standards & Engagement, and UL Research Institutes.
UL Standards
Sustainability Standards
* UL 106, Standard for Sustainability for Luminaires (under development)
* UL 110, Standard for Sustainability for Mobile Phones
Standards for Electrical and Electronic Products
* UL 50, Enclosures for Electrical Equipment
* UL 50E, Enclosures for Electrical Equipment, Environmental Considerations
* UL 153, Portable Electric Lamps
* UL 197, Commercial Electrical Cooking Appliances
* UL 244B, Field Installed and/or Field Connected Appliance Controls
* UL 410, Slip Resistance of Floor Surface Materials
* UL 796, Printed-Wiring Boards
* UL 916, Energy Management Equipment
* UL 962, Household and Commercial Furnishings
* UL 962A, Furniture Power Distribution Units
* UL 962B, Outline for Merchandise Display and Rack Mounted Power Distribution Units
* UL 970, Retail Fixtures and Merchandising Displays
* UL 1026, Electric Household Cooking and Food Serving Appliances
* UL 1492, Audio/Video Products and Accessories
* UL 1598, Luminaires
* UL 1642, Lithium Batteries
* UL 1995, Heating and Cooling Equipment
* UL 2267 Standard for Safety - Fuel Cell Power Systems for Installation in Industrial Electric Trucks
* UL 6500, Audio/Video and Musical Instrument Apparatuses for Household, Commercial and Similar General Uses
* UL 60065, Audio, Video and Similar Electronic Apparatuses: Safety Requirements
* UL 60335-1, Household and Similar Electrical Appliances, Part 1: General Requirements
* UL 60335-2-24, Household and Similar Electrical Appliances, Part 2: Particular Requirements for Motor Compressors
* UL 60335-2-3, Household and Similar Electrical Appliances, Part 2: Particular Requirements for Electric Irons
* UL 60335-2-34, Household and Similar Electrical Appliances, Part 2: Particular Requirements for Motor Compressors
* UL 60335-2-8, Household and Similar Electrical Appliances, Part 2: Particular Requirements for Shavers, Hair Clippers and Similar Appliances
* UL 60950, Information Technology Equipment
* UL 60950-1, Information Technology Equipment – Safety, Part 1: General Requirements
* UL 60950-21, Information Technology Equipment – Safety, Part 21: Remote Power Feeding
* UL 60950-22, Information Technology Equipment – Safety, Part 22: Equipment to be Installed Outdoors
* UL 60950-23, Information Technology Equipment – Safety, Part 23: Large Data Storage Equipment
* UL 62368-1, Audio/Video, Information and Communication Technology Equipment – Part 1: Safety Requirements
Life Safety Standards
* UL 217, Single- and Multiple- Station Smoke Alarms
* UL 268, Smoke Detectors for Fire Protective Signaling Systems
* UL 268A, Smoke Detectors for Duct Application
* UL 1626, Residential Sprinklers for Fire Protection Service
* UL 1971, Signaling Devices for the Hearing Impaired
Standards for Building Products
* UL 10A, Tin-Clad Fire Doors
* UL 20, General-Use Snap Switches
* UL 486E, Equipment Wiring Terminals for Use with Aluminum and/or Copper Conductors
* UL 1256, Fire Test of Roof/Deck Constructions
Standards for Industrial Control Equipment
* UL 508, Industrial Control Equipment
* UL 508A, Industrial Control Panels
* UL 508C, Power Conversion Equipment
* UL 61800-5-1, Adjustable Speed Electrical Power Drive Systems
Standards for Plastic Materials
*
UL 94, Tests for Flammability of Plastic Materials for Parts in Devices and Appliances
* UL 746A, Polymeric Materials: Short-Term Property Evaluations
* UL 746B, Polymeric Materials: Long-Term Property Evaluations
* UL 746C, Polymeric Materials: Use in Electrical Equipment Evaluations.
* UL 746D, Polymeric Materials: Fabricated Parts
* UL 746E, Polymeric Materials: Industrial Laminates, Filament Wound Tubing, Vulcanized Fiber and Materials Used in Printed-Wiring Boards
* UL 746F, Polymeric Materials: Flexible Dielectric Film Materials for Use in Printed-Wiring Boards and Flexible Materials Interconnect Constructions
Standards for Wire and Cable
* UL 62, Flexible Cords and Cables
* UL 758, Appliance Wiring Material (AWM)
* UL 817, Cord Sets and Power Supply Cords
* UL 2556, Wire and Cable Test Methods
UL Solutions of Canada

* CAN/ULC-S101-07, Standard Methods for Fire Endurance Tests of Building Construction and Materials
* CAN/ULC-S102-10, Standard Methods of Test for Surface-Burning Characteristics of Building Materials and Assemblies
* CAN/ULC-S102.2-10, Standard Methods of Test for Surface-Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies
* CAN/ULC-S104-10, Standard Methods for Fire Tests of Door Assemblies
* CAN/ULC-S107-10, Standard Methods for Fire Tests of Roof Coverings
* CAN/ULC-S303-M91 (R1999), Standard Methods for Local Burglar Alarm Units and Systems
Photovoltaic
*
UL 1703, Photovoltaic Flat-Plate Modules
*
UL 1741, Inverters, Converters, Controllers and Interconnection System Equipment for Use With Distributed Energy Resources
*
UL 2703, Rack Mounting Systems and Clamping Devices for Flat-Plate Photovoltaic Modules and Panels
Recognized Component Mark

The Recognized Component Mark is a type of safety certification mark issued by UL Solutions. It is placed on
components which are intended to be part of a UL certified end product, but which cannot bear the full UL
Mark
Mark may refer to:
Currency
* Bosnia and Herzegovina convertible mark, the currency of Bosnia and Herzegovina
* East German mark, the currency of the German Democratic Republic
* Estonian mark, the currency of Estonia between 1918 and 1927
* F ...
themselves. The general public does not ordinarily come across it, as it is borne on components which make up finished products.
Computer benchmarking
UL offers the following computer benchmarking products:
*
3DMark
* Easy Benchmark Automation
* PCMark 10
* PCMark for Android
* Servermark
* Testdriver
* UL Procyon AI Inference Benchmark
* UL Procyon Photo Editing Benchmark
* UL Procyon Video Editing Benchmark
* VRMark
Similar organizations
;
Applied Research Laboratories (ARL)
: A competing testing laboratory, based in Florida, U.S.
;
Bureau Veritas
Bureau Veritas is a French company specialized in testing, inspection and certification founded in 1828. It operates in a variety of sectors, including building and infrastructure (27% of revenue), agri-food and commodities (23% of revenue), ma ...
: A competing test, inspection, and certification company.
;
Baseefa
: A similar organization in the United Kingdom.
;
Canadian Standards Association (CSA)
: A similar organization in Canada. Also serves as a competitive alternative for U.S. products.
;
CCOE
: Chief Controller of Explosives
;
CEBEC
: Testing laboratory, inspection, and certification company, based in Brussels, Belgium.
;
DNV GL
: A global testing laboratory, inspection, certification, marine class, and engineering organisation, headquartered in Høvik, Norway.
;
Efectis
: A similar organization in Europe, fire science expert, testing laboratory, and certification body.
;
ETL SEMKO
: A competing testing laboratory, part of
Intertek; based in London, U.K.
;
FM Approvals
: A competing certification body, based in Rhode Island, U.S.
;
ICC-ES
: International Code Council Evaluation Services.
;
IAPMO R&T
: A competing certification body, based in Ontario, California, U.S.
;
INERIS
: Testing laboratory, inspection, and certification company, based in France.
;
KFI
: The Korea Fire Institute, a similar organization in Korea.
; MET Laboratories, Inc.
: A competing testing laboratory, based in Baltimore, Maryland, U.S.
MiCOM Labs (MiCOM): A consumer, wireless, telecom, IT, medical, and aerospace industry, testing, and certification laboratory, based in Pleasanton, California, U.S.
;
NTA Inc
: A certification agency based in Nappanee, Indiana, U.S.
QAI Laboratories (QAI): A competing certification body, with locations in Canada (Vancouver, BC - HQ and Vaughan, ON); United States (Rancho Cucamonga, CA and Tulsa, OK); Seoul, South Korea; and Shanghai, China.
QPS Evaluation Services: A competing testing and certification body for product safety (NRTL, ATEX, IECEx, CB Scheme and Field Evaluations).
;
Sira
: A similar organization for the UK/Europe.
;
GS
:
Geprüfte Sicherheit
;
TÜV
: German and Austrian approvals organizations.
Cardno PPI: A similar third party organization, with offices in Houston, Texas, U.S.; Lafayette, LA, U.S.; London, U.K.; and Perth, Australia.
See also
*
ANSI
The American National Standards Institute (ANSI ) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organ ...
*
CE marking
*
Conformance mark
* ''
Consumer Reports
Consumer Reports (CR), formerly Consumers Union (CU), is an American nonprofit consumer organization dedicated to independent product testing, investigative journalism, consumer-oriented research, public education, and consumer advocacy.
Founded ...
''
*
Consumers Union
A consumer is a person or a group who intends to order, or uses purchased goods, products, or services primarily for personal, social, family, household and similar needs, who is not directly related to entrepreneurial or business activities. ...
*
Fire test
A fire test is a means of determining whether fire protection products meet minimum performance criteria as set out in a building code or other applicable legislation. Successful tests in laboratories holding national accreditation for testing and ...
*
Good Housekeeping Seal
''Good Housekeeping'' is an American women's magazine featuring articles about women's interests, product testing by The Good Housekeeping Institute, recipes, diet, and health, as well as literary articles. It is well known for the "Good House ...
*
National Sanitation Foundation
*
NEMKO
*
Product certification
*
Quality control
*
RoHS
*
Safety engineering
Safety engineering is an engineering discipline which assures that engineered systems provide acceptable levels of safety. It is strongly related to industrial engineering/systems engineering, and the subset system safety engineering. Safety eng ...
*
Société Générale de Surveillance
References
External links
*
List of US NRTLsat OSHA
{{authority control
Certification marks
Commercial laboratories
Companies based in Northbrook, Illinois
Electrical safety standards organizations
Laboratories in the United States
Organizations established in 1894
Product-testing organizations
Standards organizations in the United States
1894 establishments in the United States