Grounding Monitor Interrupters On RVs and Their Impact On RV Parks And Campgrounds

The 2026 Edition of the National Electric Code (NEC) is now published, which finalizes the grounding monitor interrupters requirement. All RVs with 30A or 50A electrical service will be required 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 the receptacle for a proper ground connection. During use, the GMI will also monitor the ground connection to the RV and, if lost, will disconnect the power to the RV.

Background on the National Electric Code, RVs, RV Parks and Campgrounds, and Grounding Monitor Interrupters

The National Electric Code governs electrical installations in the United States. It is updated and published by the National Fire Protection Association (NFPA) every three years. Article 551 of the National Electric Code contains the electrical requirements for both RVs and RV Parks and Campgrounds. These requirements work hand in hand to ensure safety for the users of both. 

Over the last 6 years, there have been several public inputs to Article 551 addressing “hot skin” conditions. 

On the RV Parks and Campgrounds side, it was suggested that Ground Fault Circuit Interrupter (GFCI) receptacles for the 30A and 50A services be installed on the RV pedestal. That suggestion was not adopted because electrical leakage current from the various electrical devices in an RV would cause a nuisance trip of the GFCI. Another suggested remedy was to install a reverse polarity device on the RV. While improving safety, a reverse polarity device fails to protect against a “hot skin” condition. In the 2023 edition of the National Electric Code, the requirement for the reverse polarity device was replaced with a requirement for a loss-of-ground device. However, because no loss of ground device existed in 2023, enforcement of the requirement was delayed to January 1, 2026. 

The loss of ground device requirement was further defined as a GMI, resulting in what will be published in the 2026 Edition of the National Electric Code as outlined above.

What is a “Hot Skin” Condition?

"Hot skin" is a term used to describe when an RV’s metal exterior, metal frame, or other metal items become electrified, which is a serious electrical safety hazard caused by improper grounding or electrical faults. The National Electric Code and the RV industry continue to improve the electrical safety of RVs for consumers through new requirements like the GMI.

What is a Grounding Monitor Interrupter?

A GMI tests the receptacle it is plugged into to ensure it is wired correctly and has a proper ground connection. If incorrect wiring or a loss of ground connection is detected, the GMI will not allow electricity to pass through or will disconnect power if the loss of ground occurs during operation. 

Is a GMI Similar to a GFCI Receptacle?

No. A GFCI receptacle monitors electrical current flowing through it. If electrical current is out of balance, it trips and disconnects electrical power. A GMI ensures that a proper ground exists.

What Things Will a GMI Address?

On the RV, the GMI will address damage to a power cord, which the National Electric Code refers to as a “feeder assembly.” Damage to a power cord and the use of dog-bone adapters, causing a compromised electrical supply, are the most common reasons for requesting this update to the National Electric Code.

On the RV parks and campgrounds side, the GMI will address a loss of ground at the RV pedestal or the presence of electrical current on the grounding conductor (wire). Under certain conditions, either of these two items can result in “hot skin.” 

When Will this New Requirement Take Effect?

The 2026 Edition of the NEC was adopted and published in late September 2025. The RV Industry Association plans to set the exact 2026 dates for adoption and enforcement of the 2026 edition at the next Board meeting in November 2025.

What Can RV Parks and Campgrounds Do to Get Ready for this New Requirement?

RV parks and campgrounds should test their electrical systems to ensure good ground continuity from the RV site pedestals back to the electrical service panels. This should be part of parks and campgrounds’ annual preventative maintenance. 

There are commercially available portable 30A and 50A RV receptacle testing devices that an RV park and campground can use to test their electrical systems for ground continuity and compatibility with RV GMIs.

What is the RV Industry Association Doing to Notify the Industry and Future Owners of this New GMI Requirement?

The RV Industry Association and its technical subcommittees have been working on implementing a GMI requirement for the past six years. In the past year, the RV Industry Association has provided regular updates to the wider OEM, supplier, dealer, and park and campground segments through newsletter articles and presentations at industry events and meetings. The Association will continue to provide updates and details relating to this issue, such as details on enforcement actions and details regarding commercially available GMI devices, as the information becomes available.