An NEC proposal is designed to protect first responders
BY JEFFREY SARGENT
FOR YEARS, firefighters have faced an electrical conundrum when they enter burning buildings: they could be exposed to energized electrical wiring, or they could risk the well-documented hazards associated with de-energizing the building’s electrical panel and wiring system, a practice known as “pulling the meter.” Lack of proper training and inadequate electrical personal protective equipment, coupled with the fact that utility revenue meters were neither designed nor intended to be a disconnecting means, have resulted in fire service personnel being injured while pulling meters.
A proposed revision for the 2017 National Electrical Code® (NEC®), however, would protect firefighters and other first responders from shock and possible arc-flash hazards while responding to certain residential incidents. The revision requires all one- and two-family homes to have a service disconnecting means, or a way to operate the service disconnecting means, on the exterior of the home. While some communities have adopted local amendments requiring exterior service disconnects, it has not been codified in the NEC. The proposed requirement has an effective date of July 1, 2020.
Removing the meter does not always interrupt a building's power, which is why standard operating procedure for first responders since the 1970s has been to not pull meters—but to say it never happens would be untrue. First responders are often faced with situations where they must do whatever it takes to mitigate a hazard, especially when lives are in jeopardy. In some locations, particularly rural areas, the time it can take for a utility crew to arrive at the fire scene can force first responders to pull the meter themselves in an attempt to disable a building's power.
Those dangers, particularly when the electrical equipment is located in a basement, provided the rationale for the proposed requirement, which did not receive the necessary two-thirds approval by the code-making panel (CMP) in the first round of the NEC revision cycle. While the majority of the panel supported it, others objected, citing security concerns, equipment location and degradation problems, and other issues.
The public comments received on the proposal, however, underscored the importance of the issue and the CMP reversed their original action and accepted the new requirement. One comment pointed out that entering a building to shut off the power creates a safety hazard for first responders not just during fires, but also in the event of flooding, gas leaks, and structural failures. While the necessary two-thirds majority of the panel supported it, there were several members who objected, citing security concerns, equipment location and degradation problems, and other issues.
In the 2014 NEC, a requirement for the rapid shutdown of photovoltaic systems was added by the code-making panel to protect firefighters against electrical hazards associated with energized PV system conductors on and in roofs as well as in buildings. Although the 2014 NEC did not contain a requirement specifying where the rapid shutdown actuation means was to be located, one approach used by a number of AHJs was to require that it be located at or near the utility meter location, or at the service disconnecting means if it was installed on the building's exterior. Where the PV system used utility interactive micro-inverters, the use of the service disconnecting means as the rapid shutdown device has been widely accepted by the enforcement community. A new requirement for outdoor service disconnecting means would allow first responders to disconnect utility and PV power from a readily accessible location outside of a one- or two-family dwelling.
It should be noted that that the die is not yet cast on this proposed change. NFPA’s codes and standards revision process permits this issue to be brought to the technical meeting at NFPA’s Conference & Expo in June as a certified amending motion. You can review the First and Second Draft Reports and any actions that occur through the remainder of the revision process by clicking on the Next Edition tab on the document information webpage.