NFPA 110: Standard for Emergency and Standby Power Systems

NFPA 110: Standard for Emergency and Standby Power Systems is a national standard covering emergency and standby power systems. Its significance in the account of Hurricane Katrina lies in the gap between having backup generators and having a power system capable of sustaining a hospital through a prolonged emergency: at Memorial Medical Center, generators and the equipment that connected them to the hospital were part of a vulnerable, interdependent system.

Scope and testing

NFPA 110 addresses emergency power systems within a broader set of electrical codes and standards for healthcare facilities. The account describes hospital generators as subject to monthly testing, but says those tests were brief. Memorial’s maintenance staff ran them once a month in the middle of the night; the generators were not designed for extended operation, even though the hospital’s disaster plan expected them to support the facility for at least three days. The Joint Commission later emphasized that meeting NFPA codes and standards was only a starting point: experience showed that systems meeting those standards could still prove inadequate in major catastrophes. In 2007, it required emergency generators to undergo a four-hour continuous test once every thirty-six months, in addition to the existing monthly, thirty-minute tests. This was a separate accreditation requirement, not a requirement attributed to NFPA 110 itself.

Memorial’s known vulnerabilities

Before Katrina, Memorial’s plant operations director, Eric Yancovich, had examined storm-surge models and sketched the elevations of hospital entrances and critical equipment against Magnolia Street. He calculated that less than four feet of street flooding could carry water over the loading dock and into the hospital. Although the generators themselves were on the second floor, important components of the emergency-power distribution system—including transfer switches and other equipment—were at or below ground level. Yancovich warned that relatively little flooding could disable most of the medical center. He expected that patients might have to be moved to the newer Clara Wing, where he believed the circuitry was better protected. The hospital had installed floodgates and raised a vent for its underground diesel tanks, but proposed work to elevate transfer switches and pumps supplying medical air and vacuum suction was not completed. A partial bid for electrical work exceeded a quarter of a million dollars; Yancovich’s memo cited a lack of capital and left the proposal on file for future consideration.

Failure during the outage

As the generators ran for a second day, Memorial’s staff faced failures they were not equipped to repair. When an engine stopped, workers initially added water to its radiator and restarted it. Later, low oil pressure was suspected; staff brought diesel in an effort to prime the motors, and retrieved more fuel from a generator at the surgery building. Meanwhile, sections of the hospital lost power and the lighting dimmed. After one generator failed, engineers tried to transfer some of its electrical load to another. They waded through knee-deep basement water to reach the electrical building and operated a bypass handle above their heads. The working generator then drew excessive current, suggesting a short circuit. Workers tried to separate the loads and shut off branch circuits to reduce demand. A second generator failed; the staff could not repair it with the available parts. After two hours of efforts, the final generator surged and died at about two in the morning on August 31, nearly forty-eight hours after Katrina made landfall near New Orleans. The precise cause of the power failure remained contested. An expert for plaintiffs concluded that floodwater had shorted transfer switches and distribution panels, consistent with Yancovich’s warning. An expert retained by Tenet attributed the shutdown to mechanical problems in the generators, which were located above the water. The distinction matters: NFPA 110 covers emergency power systems, but the account does not establish that the standard alone explains the failure or resolves the experts’ disagreement. The generators, transfer switches, distribution panels, and other supporting equipment formed a system whose ability to deliver power depended on more than the generators’ location or rated capacity.

Standards and disaster readiness

The account places NFPA 110 within a larger discussion of preparedness for prolonged emergencies. The standards in force at the time called for flooding and other local hazards to receive careful consideration in electrical-system design. Revised National Fire Protection Association standards issued in 2012 strengthened this language, saying systems should be designed to protect against such hazards; as of June 2013, however, hospital regulators had not yet adopted them. The distinction between published standards and their adoption by regulating bodies shaped what facilities were expected to do. The experience also showed the limits of routine testing when the expected emergency lasts far longer than a test. Monthly checks lasting minutes could establish that equipment operated briefly without demonstrating how a system would perform under days of continuous demand, flooding, or failures in connected components. Generator failures during later prolonged utility outages, including Hurricanes Gustav, Isaac, and Sandy, were cited as evidence that hospital and nursing-home systems could remain inadequate. NFPA 110 therefore appears not as a guarantee of uninterrupted care, but as part of the technical and regulatory framework whose requirements, implementation, and assumptions determine how much backup power can actually protect patients.