Many end-users and electrical contractors in the United States widely believe the "UL" marking dominate the "Listed" electrical equipment compared with the "CSA" and "ETL" marking. Actually they are the same. Underwriters Laboratories (UL), CSA group (CSA) and Intertek Testing (ETL) are both independent third-party Nationally Recognized Testing Laboratory(NRTL) to test and evaluate the products for compliance to harmonized Canadian Electrical Code(CEC) and National Electrical Code(NEC) standards.
The subscript "us" in the mark "cCSAus" and "cETLus" indicate the test is certificated in accordance with the approximate American National Standard like not limited to the National Fire Protection Association (NFPA) and National Electrical Code(NEC), No matter a products listed with "ULus", "CSAus" or "ETLus", end-users in the United States should be completely confident for the compliance and quality.
In current list of NRTLs published by Occupational Safety and Health Administration (OSHA) program, testing and certification bodies including UL, CSA and Intertek are authorized to judging the suitability of the electrical equipment to the appropriate American National Standards.
Varied test standards determined to be appropriate for use in different products segments under OSHA's NRTL Program, here are some standard codes for electrical equipment for use in hazardous locations.
CSA C22.2 No.137 Electric Luminaires for Use in Hazardous Locations
CSA C22.2 No. 174 Cables and Cable Glands for Use in Hazardous Locations
While UL listed products can be acceptable in the United States and globally, CSA listed products are not only for use in Canada, ETL listed products are not only for use in the United States, when marked with "us" and/or "c", both UL, CSA and ETL can be used domestically and globally. Follow three groups of images to illustrate the details:
For use in U.S.
For use in Canada
For use both in U.S. and Canada
Test by UL
Test by CSA
Test by Intertek
Standards Development Organizations stands for SDOs, develop and amend the technical specifications and standards for electrical equipment to ensure the significant operation safety, widely be looked up by products manufacturers and testing laboratories.
In the United States, the American National Standard Institute(ANSI) is the organization for promulgating the American National Standards for electrical equipment, ANSI assigned UL as the SDO to develop the mentioned standard, such as UL844 standard. Electric Lighting Fixtures for Use in Hazardous (Classified) Locations.
In Canada, the Standard Council of Canada authorized CSA group to develop Canadian National Standard, such as CSA C22.2 the installation and maintenance of electrical equipment in Canada.
Certificate Bodies are the third-party testing laboratories and certificate issue bodies who are authorized to perform test and certification for products manufacturer, such as UL, CSA and ETL are all recognized certificate bodies.
UL Does Not Mean "U.S." Only
UL serve UL standard in the United States as SDO, when as a certificate body, UL not only issue UL certificate in accordance with itself UL standard but also issue UL certificate in accordance with CSA standard (with subscript "c").
CSA Does Not Mean "Canada" Only
CSA serve CSA standard in Canada as SDO, when as a certificate body, CSA not only issue CSA certificate in accordance with itself CSA standard but also issue CSA certificate in accordance with UL standard (with subscript "us").
ETL is not SDO when as a certificate body, ETL not only issue ETL certificate in accordance with UL standard (with subscript "us") but also issue ETL certificate in accordance with CSA standard ( with subscript "c").
Standards are available for any qualified manufactures and laboratories to select to perform a test or certification before it enters to the market, based on the same testing standards, different certificate bodies perform the same test requirements regardless of which laboratory performs the test.
In the United States, all Nationally Recognized Testing Laboratories (NRTLs) are required to perform the same testing procedures and standards code for electrical equipment. Whether certificate body is UL, CSA, ETL or any other NRTL, it really makes no difference with regard to the standards it is required to meet. Therefore, when you see ETL Listed versus UL Listed on a product, both essentially mean the same certificate. Nevertheless, there is still an existing recognition "prestige" for UL listed exactly because UL actually is also SDO developing its own UL standards, now it is time for us to say "no" to limit a request "only UL Listed", but start to prefer "CSA to UL standard" or "ETL to UL standard" to consider more excellent products with proper cost, lead time and performance.
SDO create the actual standards for electrical equipment for test to ensure safety use.
OSHA recognize testing and certification laboratories in accordance with certain standards.
Manufacturers design the electrical equipment in accordance with certain standards.
Testing laboratories recognized by OSHA test products and issue test reports in accordance with certain standards.
Testing laboratories recognized by OSHA issue the certificate mark
Certificated electrical equipment enter the U.S. market