Electrical, Power

Backup, standby and emergency power for hospitals

In this wrap-up of an education session, learn about the basics of designing power systems in hospitals

By Richard A. Vedvik and David Stymiest August 10, 2021
Courtesy: IMEG Corp.

When designing backup, standby and emergency power systems for hospitals, there are several considerations beyond NFPA 70: National Electrical Code and other building code requirements that must be addressed. Electrical engineers must understand the specific owner project requirements for the building’s power systems and ensure that the generator specification and system topologies meet all those requirements for cost, construction schedule, component performance and system maintainability.

Engineers also need to be mindful of the construction process, and ensure equipment replacement is coordinated, temporary power strategies are identified and phasing concepts are developed.

Learning objectives:

  • Know the codes and standards that define the design of emergency, standby and backup power systems.
  • Identify important qualities and characteristics of generators for hospitals beyond the standard National Electrical Code and building standards.
  • Learn best practices for specifying power systems and identify commonly seen specification errors or omissions.
  • Review and compare various design topologies and solutions often seen implemented for hospitals. Discuss why certain solutions may be more or less favorable.

Presented by:

  • Richard A. Vedvik, PE, Senior Electrical Engineer/Acoustics Engineer/Senior Associate, IMEG Corp., Rock Island, Ill.
  • David Stymiest, PE, CHFM, CHSP, FASHE, Senior Consultant, Smith Seckman Reid, New Orleans

David Stymiest: I’m required to tell you that you will hear some opinions will be mine and not the official position of the NFPA or any of its technical committees and shall not be considered to be nor relied upon as a formal interpretation. The reason for this is that I’m a primary voting member of the NFPA technical committee on emergency power supplies, which is responsible for NFPA 110 and 111.

Today, I want to start off by talking about the authority having jurisdiction, the different types of authority having jurisdiction and their impact on the requirements. I’m going to start with the federal agencies, the agencies of U.S. government, including Department of Defense, Veterans Health Administration, Indian health system and others. And these agencies, I’m not going to talk about one agency until I get to the bottom of this slide, but these agencies choose to be accredited by The Joint Commission.

They’re not required to be accepted, made the decision to be accredited by The Joint Commission, because they do not report to Centers for Medicare and Medicaid Services, which we will talk about in a moment. They’re not required to follow the edition of the codes that CMS adopts. Generally, the federal agencies will adopt new editions of the life safety code and related codes and standards shortly after the NFPA publishes those editions. The state and local authorities having jurisdiction, depending upon the state, depending upon the locality, sometimes adopt their own versions of the codes and standards. And because the codes and standards are… they’re not documents that stay the same, most of the NFPA codes and standards, the vast majority of them actually follow what CMS adopts, simply because it’s easier. But there are state and local authorities having jurisdiction that will also adopt whatever edition of the code and standards they wish to have.

The building codes is also an authority having jurisdiction, as is any local state or national authority that adopt the Facilities Guidelines Institute and the FGI guidelines. CMS is an arm of health and human services. Most of you are familiar with health and human services because Centers for Disease Control and Prevention is another arm of health and human services. The CMS is presently working from the 2012 edition of the life safety code and the 2012 edition of the health care facilities code. And with those two documents, those two codes also have hundreds of other NFPA codes and standards that they invoke. All of these requirements are not identical. They’re not the same.

It depends upon the codes and standards. It depends upon the authorities having jurisdiction. The last CMS thing I want to talk about is the CMS emergency Preparedness Final Rule that was adopted by CMS back in 2016. And it applies to every single health care facility that gets Medicare, Medicaid reimbursement from the federal government.

The terminology that we need to understand is that there are differences, unfortunately to some, there are differences. NFPA 99 is the health care facilities code. NFPA 99 basically states that it applies wherever health care is performed on humans except in their home. NFPA 70 is the National Electrical Code, both of these documents refer to an alternate power source and alternate power source could be one or more generator sets on-site, could be one or more battery, yes, on-site. In some cases, if a health care facility particularly governed by NFPA 99 is connected to its own generator system or a local generator system, when it occurs, it occurs most frequently in large cities with a large number of health care facilities near one another. In those cases, the local generator can be considered to be the main power source of one or more health care facilities.

It’s not frequent, but it’s an acceptable approach. In those cases, the utility source could be the alternate power source. So that’s one case where an alternate power source could be a generator. If the utility source is the main electrical power source for a health care facility and your alternate power source could be your utility if a large generating plant that’s local to the health care facilities is indeed the main power source. So, the alternate power source could be either. Now, both NFPA 99 and NFPA 70 have what’s called an essential electrical system. The essential electrical system includes the alternate power source and all of the distribution from that system all the way down to the loads, and by loads, I mean perhaps the red outlet, I mean the emergency light or any other important piece of health care, either health care equipment, medical equipment or facilities equipment, the physical infrastructure.

So those two phrases, alternate power source might be a generator or it might be a utility in certain cases. The essential electrical system includes the alternate power source and then goes all the way downstream to the loads. NFPA 110 does not apply unless NFPA 99, NFPA 70 or another NFPA document invokes NFPA 110. And if the alternative power source is a generator in the vast majority of cases, then even 99 or 70 or some other code and standard will indeed invoke NFPA 110. The generator set is an emergency power supply, that’s the phrase. In this particular case, if the alternate power source of the generator, then the emergency power supply is also the same generator and you have both, that’s the term that apply to the same equipment.

The emergency power supply system on the other hand is not the same as the essential electrical system. The essential electrical system goes, it starts at the generators up in the NFPA 99, NFPA 70 and goes all the way downstream to the load with the emergency power supply system. And this is the NFPA 110 description, it starts if the generator, whatever makes the generator run and goes all the way downstream to the load terminals of the transfer device, which in the vast majority of cases is the transfer switch. Within a health care system that means that the emergency power supply system, which start at the load terminals of the transfer switch does not include the power system further downstream all the way to the loads. The essential electrical system on the other hand does. I mean, next slide please.

NFPA 101, the life safety code in two of its chapters, Chapter 7 is the chapter I mean to regress, Chapter 9 is the chapter of building service and fire protection, which also includes utilities. Those two chapters actually invoke NFPA 110. In the case of the 2012 NFPA 101, it’s the 2010 edition of 110 which is invoked. NFPA 70 has article 517 that refers to health care facility, article 700, emergency systems, article 701, legally required standby systems and article 702 optional standby systems. Rich, I believe you have a question about NFPA article 700, would you try to address that now?

Richard Vedvik: Absolutely. So, my question relates to your experience when we have a TIA that makes a revision to a section, for example, the 2017 edition of NEC had a 700.10(D)(3), which referenced health care facilities and occupancies under the fire rated section on emergency power. But then that was removed a year and a half later on a TIA and code officials might actually be looking at a book that has the old version. How do you see that adoption take place when there’s a TIA that makes a change like that?

David Stymiest: Well, there’s a TIA that makes a change like that, basically it’s really up to the code official could determine and the reason that I’m saying that, is that looking at CMS, the vast majority of health care facilities or these hospitals for sure, in America they’re actually required to comply with CMS requirements. And CMS requirements apply to any facility that receives Medicare, Medicaid reimbursement from the federal government. In this context, the federal government is by far the largest insurer in America at least for health care insurance. In this particular case, CMS adopted the 2012 codes about three years or so after the codes were published by the NFPA. And when CMS adopted the codes, it did adopt TIA, Tentative Interim Amendments, but only those which were published when CMS started the process of obtaining public input. And the reason it did not adopt any other TIA, anything that was published after CMS started getting public input, was because its position is, if the public does not participate in a review of the TIA that means the CMS considers itself to be prohibited from adopting changes that did not receive public input.

So basically, in a case like this, even the 2017 edition for example or the TIA that came out in 2017, that’s not adopted by CMS because CMS simply is not using that version of the code yet. At some point, the industry expects that CMS will adopt a newer version. The last time it did it, it was noticing and comment rulemaking, notice and comment rulemaking took over a year. It may well be the same way this time. So, the TIA may be adopted by local authorities having jurisdiction. They may not be adopted by the federal authorities having jurisdiction, in this case, CMS or any accrediting agency that accredits on behalf of CMS. So that’s something which you may have two different requirements that appear to say different things, even though one of them has been changed.

Basically, in the case of two different requirements from two different AHJs or more than two different AHJs, you always have to comply with the more stringent requirement. Within NFPA 99, we have the essential electrical system type one, two and three. Type one is the more stringent. It’s the one that applies to such things as systems that feed life safety and other types of equipment whose failure could cause severe injury to patient or staff. NFPA 110 is the standard on emergency standby power system. NFPA 111 is the store electrical energy emergency and standby power systems standard.

Within the NFPA 110 chapters, basically Chapter 4 is a very short chapter. It’s a chapter that classifies the requirements and the class is hours at rated load without refueling. Now, presently in the 2010 edition of 110, there is a requirement for 96 hours, but not everywhere. It’s only 96 hours in certain seismic zones. After the 2010 edition was published, when we published the 2013 edition that requirement was actually removed and moved to the annex. However, because the 2010 edition of 110, is the one that’s invoked by the 2012 standards, then that basically still invokes the 96-hour requirement in certain seismic zone. It’s social and seismic zone. The type, the classification type is how many seconds of interruption are allowed. In most cases or the very important load is life safety, fire protection and many other loads.

Ten seconds is the maximum interruption is permitted and the level … there’s two different levels, there used to be three levels in NFPA 110, one, two and three. One is the most severe level. Again, it’s the equipment which failure could result in injury. The other main chapters in NFPA that I want to talk about are five, six, seven and eight. Five is the chapter that talks about the emergency power supply. What’s that? That’s the generator. It’s the source. It’s the converters. It’s the accessories that help the generator run. Six is the transfer switch equipment, seven is the installation and environmental consideration that discusses, for example, what can go in a generator room, what can go with transfer switches, things of that nature. And eight is the routine maintenance and operational testing. So, from NFPA 110, the standard that is important, Chapter 7 has the requirement on installation acceptance testing.

When installation acceptance test, it is quite substantial and not everyone understands it. But when that test is completed, the one-time requirement is it’d be followed immediately by the first monthly load test that’s required by Chapter 8. You cannot do the first load test. The first load test starts as soon as the installation acceptance test is completed. Chapter 7 and eight also include requirements for weekly inspections of the entire emergency power supply system, load tests of the entire EPSS and you will test it only if required. That means only if the monthly results don’t get the generator loading up to 30% and a three- or four-hour load tests, which is the final requirement.

Figure 8: Operating rooms require sufficient space to allow for the patient, hospital staff and medical equipment. They include overhead booms to deliver utilities to the patient area. Courtesy: IMEG Corp.

Figure 8: Operating rooms require sufficient space to allow for the patient, hospital staff and medical equipment. They include overhead booms to deliver utilities to the patient area. Courtesy: IMEG Corp.

The last item I want to talk about with respect to Chapter 8 is that the routine maintenance operational testing program actually is required to comply with all four bullets. The manufacturer’s recommendation, the instruction manuals, the minimum requirements of Chapter 8 and the authority having jurisdiction. Finally, I would like to talk about a couple of ASHE resources. ASHE is the American Society for health care Engineering. For those of you who are ASHE members, you can obtain those two monographs as PDF for free. If you’re not an ASHE member, you would … if you want the monograph, you would have to go to the American Hospital Association bookstore and purchase the monographs. But if you are an ASHE, you can obtain those monographs as PDFs for free.

Richard Vedvik: Now, one of the questions I get pretty frequently is if I may be occupancy, meaning I have health care services, but I don’t care for patients longer than 23 hours at a time. So, for example, an ambulatory surgery center where you have operating rooms that are clearly providing critical care, but it’s at the occupancy. It’s a common concept that we see. Well, it’s at the occupancy, does that mean it has to comply with 517? And it comes back to what David talked about. The category assignment still applies. If I’ve category of one or two spaces or types of spaces in which loss of life can occur, then that’s what’s going to push an AHJ to trigger 517 and NFPA 99.

We also get asked about critical access hospitals. And what I’ll say about smaller facilities or anytime you have multiple occupancies mixed into one building, be aware of whether or not your emergency equipment, your EPSS or EPS can be located in a B occupancy and then serve an ITU. Typically, that’s not going to be the case, you’re going to want to locate in the ITU and then back feed the B occupancy and remodel that really matters. Now David talked about alternate power sources and what can they be? Well, we see here a list of what is typical, right? NEC allows for fuel cells and batteries and yet NFPA 110 is going to talk about natural gas generators and diesel generators. Now, David, even though we see NFPA 853 here, what can we see coming up about fuel cells?

David Stymiest: Right now, the second proposal, second proposed, basically phase of the NFPA 110, 2022 edition is out there for public comment. If you go to nfpa.org/110nextedition, you can actually read what has been proposed in 2022 edition. We’re in the phase basically that determines whether or not anyone is going to want to propose basically a notice of intent to make a motion during the NFPA annual conference this summer. Right now, the 2022 edition is proposed to allow fuel cells as emergency power supplies. Back to you Rich.


Richard A. Vedvik and David Stymiest
Author Bio: Richard A. Vedvik, PE, Senior Electrical Engineer/Acoustics Engineer/Senior Associate, IMEG Corp., Rock Island, Ill. David Stymiest, PE, CHFM, CHSP, FASHE, Senior Consultant, Smith Seckman Reid, New Orleans