Health care emergency power systems can have very different requirements, depending on the code editions adopted by accrediting organizations and the local authorities having jurisdiction.

Most health care facilities’ observers anticipate that the Centers for Medicare & Medicaid Services (CMS) will adopt the 2012 editions of the National Fire Protection Association’s Life Safety Code (NFPA 101) and Health Care Facilities Code (NFPA 99) within the next year or so.

The accrediting organizations, such as the Joint Commission, also are expected to adopt those same two code editions as soon as CMS adopts them. When the adoption of updated codes finally happens, there will be substantial changes affecting emergency power system management in health care facilities.

Reference issues

One key to understanding the breadth of the changes is to remember that these new sets of codes will reference other codes affecting emergency power systems.

Life Safety Code (LSC) references. The main reason for these changes is that the 2000 LSC references the 1999 edition of the Standard for Emergency and Standby Power Systems (NFPA 110) and the 1996 edition of the Standard on Stored Electrical Energy Emergency and Standby Power Systems (NFPA 111). The 2012 editions of both codes, however, reference the 2010 editions of NFPA 110 and NFPA 111. This is because when a new or revised NFPA standard references other NFPA standards, the edition that it references is the latest official edition in effect when the standard is approved and issued by the NFPA standards council. [The details can be found in the beginning of NFPA standards under Chapter 2, Referenced Publications, within Section 2.2, NFPA Publications.]

The 2012 LSC has several direct references to emergency power standards. Paragraph states that emergency generators providing power to emergency lighting systems shall be installed, tested and maintained in accordance with NFPA 110 (2010). It also states that stored electrical energy systems, where required in the LSC, other than battery systems for emergency luminaires in accordance with, shall be installed and tested in accordance with NFPA 111 (2010).

In Chapter 9, Paragraph states that emergency generators and standby power systems shall be installed, tested and maintained in accordance with NFPA 110. Also in Chapter 9, Paragraph 9.1.4 states that stored electrical energy systems shall be installed, tested and maintained in accordance with NFPA 111.

Health Care Facilities Code references. The 2012 edition of NFPA 99 references the NFPA 110-2010 inspection, testing and maintenance requirements within subparagraphs of Section It also references NFPA 111 maintenance and testing requirements within Paragraph and in Paragraph Furthermore, there are numerous mandatory extracts from NFPA 110-2010 inserted into NFPA 99-2012.

National Electrical Code (NEC) references. The 2012 edition of NFPA 99 also includes, within Paragraph Electrical Systems, the extracted NFPA 101-2012 Paragraph 9.1.2 statement that new electrical wiring and equipment shall be in accordance with the 2011 edition of the National Electrical Code (NFPA 70). The 2011 NEC also references the 2010 edition of NFPA 110 for performance, testing and maintenance requirements.

The 2011 NEC includes numerous changes in installation criteria since the 2000 LSC was adopted. The NEC is issued every three years, and includes many more changes per update than any other NFPA code or standard. Because the NEC consists of installation requirements, most health care facilities that have undergone construction or renovation projects already have experienced those changes after they occurred because modern building codes typically reference other modern codes.

However, one issue that bears watching is the difference in electrical content between the 2012 NFPA 99 edition and the 2011 NEC edition. Because those two codes are on different update cycles, the NEC did not align itself with the important 2012 NFPA 99 electrical changes until 2014. Although there are some major differences (with one of the more important ones being changes in protective coordination requirements) between the 2012 NFPA 99 and the 2011 NEC, there should not be much impact from an accreditation compliance perspective.

Other changes

Beyond the references, health facilities professionals should be aware of several other major emergency power changes emanating from the expected codes updates.

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Major NFPA 110 changes. Many chapter numbers changed between 1999 and 2010. That means the most commonly referenced NFPA 110 requirements on monthly, annual and 36-month testing now will be found within Chapter 8 on routine maintenance and operational testing. Chapter 8 now also applies to both new and existing systems.

NFPA 110 changed test loading percentages and testing durations from absolute units (25 percent, 30 percent, 50 percent; or 30 minutes) to “not less than” (NLT) clarification language throughout, so that facilities will no longer be penalized for exceeding the minimum requirements of the standard.

Another important change in monthly testing is the change that takes effect when facilities use the percentage loading criterion instead of the exhaust temperature criterion.

The 1999 edition required 30 minutes minimum under operating temperature conditions “or” at NLT 30 percent of the generator nameplate rating. The 2010 edition requires 30 minutes minimum under operating temperature conditions “and” at NLT 30 percent of the generator nameplate kilowatt rating. The change from “or” to “and” means the engine must warm up to operating temperature before the 30-minute clock starts.

The requirements for testing after repairs now include detailed instructions, including the new requirement to transfer all automatic transfer switches (ATSs) for NLT 30 minutes. That sounds like a special monthly test.

The installation acceptance test in Section 7.13 was rewritten and improved in the 2010 edition to clarify many previous sources of questions. And the first routine test now must be performed immediately after passing the installation acceptance test.

The annual load test changed from two hours (25 percent for 30 minutes, then 50 percent for 30 minutes, then 75 percent for 60 minutes) to 1.5 hours (NLT 50 percent for NLT 30 minutes, then NLT 75 percent for NLT 60 minutes). In effect, the first 30 minutes at 25 percent was dropped. And the annual load test (intended to mitigate the potential for wet stacking of lightly loaded diesel engines) only applies to diesel generators. CMS already has addressed these two changes through its categorical waiver process.

The three-year, four-hour load test, which came into play in the 2005 edition, is now stipulated as four continuous hours including a transfer of all transfer switches, with NLT 30 percent loading or the diesel engine manufacturer’s recommended exhaust gas temperatures. Spark-ignited engines only have to use the available loads for this test. Note that NFPA 110 has required the transfer of ATSs during this test since 2005, although many Joint Commission-accredited hospitals only use load banks in accordance with the Joint Commission’s “static load” option.

The 2010 edition of NFPA 110 also stipulates the rules to follow when combining the annual load test with a three-year, four-hour load test.

The 2010 NFPA 110 language includes the requirement for annual fuel quality testing “using tests approved by ASTM International standards” — this resulted in many questions to NFPA staff. Although the 2013 edition is not likely to be referenced for accreditation purposes anytime soon, the 2013 edition has many improvements and clarifications (tanks, piping, quality, storage, testing and maintenance) in both the standard’s mandatory language and also in the Annex recommendations and informational language. The new and revised 2013 edition Annex notes are recommended reading regardless of their accreditation status.

Although the NFPA 110 requirements for all emergency power supply system (EPSS) equipment maintenance continue to reference the manufacturer’s recommendations along with other requirements, there is now a new set of recommendations for major annual maintenance of transfer switches in the NFPA 110 Annex. Remember that Annex language in NFPA standards is not mandatory language. New requirements were also mandated for paralleling switchgear maintenance.

NFPA 110 states that it does not apply to systems that are not Level 1 or Level 2 systems. Generally, those excluded systems would be NEC Article 702 Optional Standby Systems.

Another change is in the minimum required amount of fuel in seismic-risk areas. In the 1999 edition, the requirement was a minimum of 96 hours without refueling if the need for the generator persists for this time period. The 2010 edition has language that was modified in 2005 to state that American Society of Civil Engineers (ASCE) 7 seismic design Category C, D, E or F areas require a minimum of 96 hours of fuel supply. NFPA 110 was modified in 2013 to make that issue optional rather than mandatory, moving it to the Annex and stating that generator sets in ASCE 7 seismic design category C, D, E or F areas should be a minimum of 96 hours without refueling if generator operation is necessary for this period.

Refer to the standard for more specific changes regarding design and operational parameters such as room and equipment temperatures, air flow, batteries, lightning protection, distribution and protection from hazards.

The 1999 edition stated that no storage was permitted in generator rooms. The 2010 edition states that parts, tools and manuals for routine maintenance and repair may be stored there.

Major NFPA 111 changes. NFPA 111 changes between 1996 and 2010 reflect primarily the vast evolution of technology in that industry segment. The 1996 edition reflected the 1990s-era technology, whereas the 2010 edition reflects more modern technology such as fuel cells, flywheel systems, close-coupled hybrid rotary systems and ultracapacitor systems. The remote annunciation requirements also were updated from the 1990s-era requirements to more modern practices such as facility or network remote annunciation.

Changes in testing include a requirement for testing after any repair or replacement, including battery replacement. The installation acceptance test is more detailed than in the 1996 edition. The stipulated stored emergency power supply system (SEPSS) exercising requirements expanded the operational testing requirements and changed the annual exercise from full load for the full duration of the class to full load for 60 percent of the class. The battery-maintenance requirements have more load test details stipulated, including required response to bad readings.

The NFPA 111 exclusions were broadened to state that an uninterruptible power supply powered by an EPSS is not an SEPSS within the scope of NFPA 111. That type of device is now broadly referenced as a bridging system or bridging equipment, intended to bridge the 10-second EPSS startup time.

Continuing to evolve

Codes affecting hospital emergency power systems continue to evolve as technology and performance data keep advancing.

Health facilities professionals should be aware of these and other upcoming changes as they attempt to keep up on the latest hospital infrastructure requirements. 

David L. Stymiest, PE, CHFM, CHSP, FASHE, is a senior consultant at Smith Seckman Reid Inc., specializing in facilities engineering and regulatory compliance. Although he is chair of the NFPA technical committee on emergency power supplies, which is responsible for NFPA 110 and 111, the views and opinions expressed in this article shall not be considered the official position of NFPA or any of its technical committees and shall not be considered to be, nor be relied upon as, a formal interpretation. He can be reached at

Looking to future code revisions

Although the 2012 editions of the National Fire Protection Association’s NFPA 99, Health Care Facilities Code, and NFPA 101, Life Safety Code, do not reference the 2013 or 2016 editions of NFPA 110 and NFPA 111, it is helpful to understand newer modifications, because they often include clarifications of existing wording or existing intent.

The 2013 edition of NFPA 110 cleared up two areas that had resulted in many questions to NFPA staff — fuel testing and maintenance, and the required amount of fuel in seismic-risk areas. It also stated that “Qualified Persons” (as defined within the standard) are the only individuals who may test and maintain an emergency power supply system (EPSS). The 2013 edition now includes Annex informational references to NFPA 70B.

It also moved around and clarified existing requirements and removed redundancies pertaining to equipment and room temperatures as well as combustion air and ventilation air.

The 2013 edition also aligned with the NFPA 99-2012 change stating that the 10-second starting time is not required to be demonstrated during monthly testing, but would then need to be confirmed annually.

The 2013 edition also stated that medium voltage central plant mechanical switching is permitted to be electrically interlocked medium voltage breakers.

The 2013 edition of NFPA 111 added requirements for DC rectifier plants. It also excludes a Level 1 stored EPSS from being located within a high-energy normal power equipment room, similar to language that has been within NFPA 110 for some time.

The 2016 editions of NFPA 110 and NFPA 111 are going through the updating and approval process. Proposed or anticipated changes are not official until the process is completed and the NFPA Standards Council approves and issues them. Draft changes can be viewed on the NFPA website.