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ANSI/UL 1449

A reference page on ANSI/UL 1449.

  • ANSI/UL 1449, 5th Edition, 2021

    This is the UL standard for safety and performance for Surge Protective Devices – SPD, for use of end-users, manufacturers, and specifiers.


    As a generalization, UL addresses electrical product safety in areas that involve a risk of fire, electric shock, or injury to persons. UL verifies the safe operation of SPDs through a listing or component recognition process including a series of stringent destructive and non-destructive tests. These ensure safe operation during normal operation and at the unit’s end of life.


    End-of-life characteristics are particularly important because SPDs are placed in harm’s way and can affect the rest of the electrical distribution system. Areas of interest include fault current testing, thermal issues, touch-safety, etc.


    Nationally Recognized Testing Laboratories (NRTLs – such as UL, CSA, Intertek, MET Labs, etc.) provide a valuable service to specifiers and end-users by testing the performance of all SPDs the same way. This is the only ‘common’ testing format in the industry, making it an important barometer of performance.

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