UL/NRTL/CSA Requirements

In the United States manufacturers may be required to certify their product(s) and equipment in accordance with various federal, state and local jurisdictions. Various safety organizations such as UL (Underwriters Laboratory) and UL approved agencies, as well as NRTLs (Nationally Recognized Testing Laboratories) are approved to provide the necessary certification labels. Recognitions between Canada and the United States now make it much easier and common for manufacturers to combine both the U.S. and the CSA (Canadian Standards Association) certifications, as necessary.

Field evaluations and listings may be necessary depending on the type and frequency of unit manufacturing.

• Field evaluations are typically carried out on equipment that is produced once. For instance a single unit electrical enclosure may be tested and labeled on either the manufacturer or customer premises.


• Listings apply to products that are regularly produced in sufficient quantity. Testing and labeling are conducted. The manufacturer applies the labels on the product, and is subject to a quarterly inspection to ensure continued compliance.

 Various safety standards from various agencies (NFPA, UL, etc …) may apply to a compliance project.