The 2015 revisions to the UL 943 require improvements in GFCI performance that will provide better protection from serious injury and electrocution from electrical shock. These improvements include:
1.) Auto-Monitoring or Self-Test function: This function allows for periodic, automatic testing of the ability of the GFCI to respond to a ground fault. If the Self-Test function detects a problem, the GFCI must deny power or provide visual and/or audible indication.
2.) Reverse line-load misfire function - repeated: If the line cable is wired to the load terminals of a receptacle GFCI, power to the receptacle face will be denied. This requirement applies to the initial installation and any subsequent re-installations.
To maintain UL certification, all manufacturers must meet these revisions with GFCIs produced after 2015.