Flip over any electronic device and you’ll notice an array of logos and acronyms, the emblems of third-party testing laboratories. These privately-owned labs test and certify manufacturers’ products to ensure that they meet the workplace safety standards upheld by the Occupational Safety and Health Administration (OSHA). For OSHA Safety Standard compliance, 37 different categories of workplace-related products (primarily electrical devices and equipment) must be certified by a Nationally Recognized Testing Laboratory (NRTL). In the US, Underwriters Laboratories (UL) is the best known of the NRTLs: so well known that it has almost become synonymous with product certification. What many do not realize, however, is that there are many other NRTLs and manufacturers have a choice in selecting the NRTL to which they submit their products. NRTLs include:

Intertek Testing Services NA, Inc. (ITSNA, originally Edison Testing Laboratories or ETL)

Canadian Standards Association (CSA/CSA International)

Communication Certification Laboratory, Inc. (CCL)

Curtis-Straus LLC (CSL)

FM Approvals LLC (FM, once Factory Mutual Research Corporation)

MET Laboratories, Inc. (MET)

NSF International (NSF)

National Technical Systems, Inc. (NTS)

SGS U.S. Testing Company, Inc. (SGSUS, once UST-CA)

Southwest Research Institute (SWRI)

TUV America, Inc. (TUVAM)

TUV Product Services GmbH (TUVPSG)

TUV Rheinland of North America, Inc. (TUV)

Underwriters Laboratories Inc. (UL)

Wyle Laboratories, Inc. (WL)

So how do manufacturers decide with whom to work for product approval? Speed, cost of certification, and customer service are major factors for manufacturers. The certification requirement of a target customer may be another factor. Here’s what OSHA has to say about the difference between the laboratories:

Given that each NRTL has met the same requirements for recognition, OSHA considers NRTLs recognized for the same product safety test standard to be equivalent in their capability to certify to that standard. For example, any NRTL recognized for ANSI Z21.16, a test standard for gas unit heaters, can certify such units for a manufacturer. However, even if recognized for the same test standards, each organization has different abilities depending on its experience, personnel, facilities and equipment, testing methods, and other aspects of its operations for testing and certifying products. OSHA only recognizes organizations as NRTLs and, under its regulations, cannot dictate how an NRTL must operate. An organization decides the detailed aspects of its own NRTL operations, although OSHA has some general policies with which NRTLs must comply.

And here’s UL’s attempt to debunk the government mandate myth:

Manufacturers submit products to UL for testing and safety certification on a voluntary basis. There are no laws specifying that a UL Mark must be used… Many companies make it their policy to obtain UL Listing not only to minimize the possibility of local non-acceptance, but also as a matter of corporate policy and commitment to minimize the possibility of risk in the use of their products.

So although the testing scope of NRTLs may vary, all NRTLs certify to consensus-based, OSHA-approved standards. Some agencies or government bodies may require a specific lab’s certification for a project, but no NRTLs are government-owned. For more information on specific testing labs and testing requirements, visit OSHA’s site.