Requirements of Hospital Generators

Requirements of Hospital Generators

Hospitals are perhaps the most deserving of reliable power delivery, as patients and facility operations can suffer without it. To keep dire situations at bay, regulatory agencies have imposed strict hospital backup generator requirements. Healthcare facilities need to meet specific, stringent standards to ensure continuous operation even in the event of a power outage.

Hospital backup generator requirements cover topics like how quickly the system must power on, how long it needs to provide power, and how rigorous testing and maintenance must be. Let’s look more closely at hospital backup generators and the standards you need to meet if you have one.

Hospital Backup Power Requirements

Hospitals are responsible for over 10% of energy consumption in the commercial sector, despite taking up less than 5% of its area. Few would argue that this hefty amount of power is unnecessary since it supports essential equipment like life-support systems, bedside alert systems, and the lights that make it possible for surgeons to do their work. It’s easy to imagine the difficulty hospitals would have without power. Even the loss of basic tools, like telephone systems or electronic records systems, can create risk as they interrupt operations and limit communication capabilities.

The severity of a hospital power outage has brought us a range of regulations, primarily from the National Fire Protection Association (NFPA). The Joint Commission, a healthcare accreditation organization, builds off of these standards and requires hospitals to undergo specific testing and maintenance requirements to achieve regular accreditation.

Although the NFPA standards are widely accepted, the NFPA does not enforce them. This is done by the authority having jurisdiction (AHJ), which varies by locality. It is often the fire marshall, but other potential authorities include labor departments or health departments.

Hospitals fall under one of the following standards and must abide by its associated regulations:


The Health Care Facilities Code considers generators a part of an essential electrical system (EES), or all of the components of a system designed to supply continuous power to the facility during power disruption. An EES also minimizes the disruption of internal wiring systems.

An organization’s EES falls under one of four different risk categories, with most hospitals falling under Category 1 due to the clear risk to patients in the event of a power outage. The NFPA splits an EES into three branches:

  1. Life safety branch: This is the branch that delivers power straight to systems needed for life safety, or allowing occupants to safely leave the building. These include the illumination of exit signs, fire alarms, and automatic doors.
  2. Critical branch: The critical branch powers circuits and equipment in certain areas that are critical to patient care, like operating rooms, patient rooms, nurseries, and nurse call systems.
  3. Equipment branch: The equipment branch serves the mechanical loads required for clinical activities. This often includes multiphase equipment like motors, compressors, and pumps that produce high-inrush currents when operated. They require an automated delayed transfer to the EES for sequential starts that prevent overloading the generators or tripping overcurrent protection devices.

Both life safety and critical branches are wired independently of other equipment with special protections. Power must be restored within 10 seconds of interruption.

Another distinction the NFPA makes is between systems described as Type 1 or 2. The two are similar but vary in their power distribution system. Hospitals have backup generators that are typically a Type 1 EES since they fall under Category 1.

NFPA 110

Under the Life Safety Code, generators — your emergency power supply (EPS) — are considered part of an entire emergency power supply system (EPSS). The entire EPSS encompasses components like transfer switches and load terminals that help deliver power. Like the Category distinctions for NFPA 99, NFPA 110 has Levels 1 and 2. Level 1 refers to systems where a power failure would result in loss of human life or serious injuries, and Level 2 systems have less critical risks.

The type of EPSS you have dictates how long it needs to stay running without refueling. NFPA 99 dictates that a hospital EES be classified as Type 10, Class X, Level 1 under NFPA 110. Class X leaves the decision of fuel capacity up to the AHJ. Typically, they require hospitals to be able to run on generator power from 24 to 96 hours.

Testing and Maintenance Requirements

Another important part of hospital generator requirements is testing and maintenance. Some tasks you need to perform include:

  • Monthly testing.
  • Yearly testing.
  • Weekly inspections.
  • Hiring and training qualified personnel to maintain and repair the generators.
  • Having the appropriate tools and instructions manuals on-site.
  • Maintaining legible labels of generators, switches, circuit breakers, etc.

Types of Generators for Hospitals and Medical Facilities

Hospitals and medical facilities can choose from several types of generators to keep the building moving:

  • Indoor generator skids: Large facilities with high power demands often use generator skids. They typically go in a dedicated room indoors, with an external fuel supply and exhaust connections.
  • Mobile generators: Generators can also be stored outdoors. Mobile generators can be moved from place to place and are a good choice when primary generators are down for repairs or maintenance.
  • Diesel generators: Diesel is one of the most powerful fuel source options and is well-suited for large facilities. These generators can reach up to 14,040 electrical kilowatts (ekW) and support a high amount of equipment. Diesel generators can meet some of the strictest standards with high efficiency and low fuel consumption.
  • Gas generators: Gas generators are less powerful, offering up to 9,700 ekW, but they are more versatile because they can accommodate various fuel sources like natural gas, propane, and alternative fuels. They allow you to choose the best option for the hospital based on availability and the cost of different fuel sources.
  • Microgrids: While not strictly generators, microgrids and solar energy systems can help deliver power if you lose access to the grid.

How Many Backup Generators Does a Hospital Have?

The number of generators required for a hospital varies widely based on the size of the hospital and generator. Some choose to meet their power demands with multiple generators, offering a secondary backup if one generator were to malfunction, but many also choose to focus on a smaller number of powerful generators. Of course, large campuses or facilities need more generators than smaller hospitals.

Hospital Backup Generators From Thompson Power Systems

A hospital’s backup generators need to be dependable and supported by professionals. Here at Thompson Power Systems, you get both. With the power of Caterpillar behind our generators, you can expect reliable performance if the power grid goes down. Our hospital backup generators come in an array of styles, all built to operate at peak efficiency and help you meet standards from the NFPA, as well as emissions requirements from the U.S. Environmental Protection Agency (EPA) and the European Union (EU).

We’ve partnered with hospitals throughout Alabama and northern Florida for over 60 years, delivering powerful generators and the support of our skilled team. We can assist with ongoing maintenance, repairs, and access to a wide parts selection. Browse our backup equipment online or reach out to us to learn more.

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