Board Sets Model Year 2028 Effective Date for GMI Enforcement

Jun 9, 2026 RV Industry Association Staff

During last week’s RV Industry Association Board of Directors Meeting, the Board voted unanimously to approve the Standards Steering Committee’s recommendation to adopt an effective date of January 1, 2027, for the requirement for all new RVs to have a grounding monitor interrupter installed and a mandatory enforcement at the start of each manufacturer’s respective model year 2028 production.

The requirement is part of the 2023 and 2026 editions of the National Electric Code (NEC) Article 551 and was scheduled to initially go into effect on January 1, 2026. It requires all RVs with 30A or 50A electrical service to install a grounding monitor interrupter (GMI), which is a loss-of-ground device. Before electrical current can pass into the RV, a GMI will check that the receptacle has a proper ground connection. During use, the GMI will monitor the ground connection to the RV and, if lost, will disconnect power to the RV. To review more information about the listing standard addressing GMIs, visit the UL site where you can read the listing standard after making a free account. 

The requirement was previously delayed because of a lack of fully developed, listed GMIs available for RV use in manufacturing at that time, making compliance with the original NEC date unrealistic. The Standards Steering Committee has continued to monitor the availability of GMIs and feel there will be availability of sufficient GMIs for use in RV manufacturing to meet the new effective date of January 1, 2027, and a mandatory enforcement at the start of each manufacturer’s respective model year 2028 production.

In the coming weeks and months there will be extensive information, education, and resources provided to manufacturers, campground owners, dealers, and consumers on what to expect from the new devices and how to prepare for their implementation.

For a full explanation of GMI, the history of the requirement, and the impact on RV parks and campgrounds, check out this article. 

Ground Monitoring Interrupters GMI