Section 230.85/Emergency Disconnects for Dwelling Units
NEC 230.85 requires an exterior emergency disconnect for one- and two-family dwellings, a major 2020 NEC addition for first responder safety.
One- and two-family dwelling units must have an emergency disconnect at a readily accessible outdoor location. The disconnect must be installed at a location that is readily accessible and in a readily accessible location outside the building. It can be the service disconnect (if located outside), a meter disconnect, or a listed emergency disconnect device. The disconnect must be marked as "Emergency Disconnect" with characters not less than 3/4 inch in height. It must disconnect all ungrounded conductors of the service. This requirement was added in the 2020 NEC to allow first responders to de-energize a dwelling from the exterior.
Why this section exists
Firefighters entering a burning dwelling need to de-energize the building to reduce electrocution risk from damaged wiring. Before this requirement, the service disconnect was often in the basement or inside a utility closet, inaccessible during a fire. The exterior emergency disconnect allows first responders to shut off power without entering the building. This also addresses electrocution risks from rooftop solar PV systems that continue generating power even when the main breaker is off.
What plan reviewers look for
Plan reviewers check the electrical site plan for the emergency disconnect location. They verify it is outdoors, readily accessible (not behind locked gates or fences), and marked per 230.85. They check that it disconnects all ungrounded service conductors. For homes with solar PV, they verify the emergency disconnect addresses both the utility service and the PV system's rapid shutdown perSection 690.12.