ETL listing means that Intertek has determined a product meets ETL Mark safety requirements.. UL listing means that Underwriters Laboratories has determined a product meets UL Mark safety requirements. Silk-screened on p... More »

Products bearing either an ETL mark or a UL mark have been certified by a Nationally Recognized Testing Laboratory, or NRTA, as compliant with the relevant minimum safety standards for that product. NRTLs are certified b... More » Business & Finance Industries Manufacturing

To receive the Electrical Testing Laboratories, or ETL, mark, a product must prove its compliance to North American consumer safety standards and pass inspection by a Nationally Recognized Testing Laboratory, or NRTL. To... More » Business & Finance Business Resources Marketing & Sales

NSF International and Underwriter's Laboratories, or UL, are separate organizations dedicated to safety standards in a variety of fields. NSF International is an independent third-party nonprofit specializing in public h... More » Business & Finance Business Resources

It is advisable to purchase a newer, electric heater that has been evaluated in a known testing facility, such as Underwriters Laboratory or Intertek, for safety. Using any type of space heater entails some risk, but man... More » Home & Garden Heating & Cooling

A UL rating refers to a product safety classification provided by the UL company. UL tests the safety of appliances and other items. Products that meet UL's standards can carry the statement "UL Listed" or "UL Classified... More » Education

Underwriters Laboratories has been doing business since 1894 when its founder, William Henry Merrill, opened the Underwriters' Electrical Bureau of the National Board of Fire Underwriters, notes The first test co... More »