NFPA 99: Electrical changes to the 2015 edition

NFPA 99: Health Care Facilities Code (2015 edition) covers a broad range of criteria for health care facilities. Electrical engineers need details about the changes to the electrical portion of the code.

By Danna Jensen, PE, LEED AP BD+C, WSP + ccrd, Dallas June 30, 2016

Learning objectives:

  • Make use of NFPA 99-2015 to design electrical systems in health care facilities.
  • List changes to the new edition of NFPA 99, specifically Chapter 6, electrical systems.
  • Explain the language of various electrical codes, including NFPA 70.

As most health care design engineers are aware, the 2012 edition of NFPA 99: Health Care Facilities Code underwent a major overhaul and complete restructuring as compared with previous editions. It introduced a new Chapter 4, which establishes "risk categories" and requires a risk assessment to be performed for health care projects. This changed NFPA 99 from being a performance-based design document to a risk-based code. In addition, NFPA 99 was renamed in 2012 from the Standard for Health Care Facilities to the Health Care Facilities Code, which upgraded it from a standard to a code, making it more adoptable and enforceable.

Now that the industry has had time to digest this major change and begin performing risk assessments, it is time for yet another edition to take effect. So what did the 2015 edition of NFPA 99 change that design engineers need to be on the lookout for? Luckily, the 2015 edition has continued to build on the risk-based approach and there were no large structural changes to this edition. However, numerous technical changes have been made throughout the document that one must be aware of.

NFPA 99 versus NFPA 70

In first reading through the changes highlighted in the NFPA 99 handbook, the authors have made a concerted effort to bring some consistency across the two major electrical health care codes: NFPA 99 and NFPA 70: National Electrical Code (NEC), with special emphasis on Article 517, Health Care Facilities. In the past, there have been several contradictions or dissimilar language that led to confusion between the two NFPA codes. However, the 2015 edition of NFPA 99 makes a discernible effort to bring the two together to complement each other, and now NFPA 99 matches much of the wording in the 2014 version of NFPA 70 Article 517.

Why does NFPA have two different codes that appear to cover the same thing? While on the surface both codes appear to cover health care electrical systems, each serves a distinct purpose.

The main purpose of NFPA 99 Chapter 6 is to define the performance required for electrical systems. Meanwhile, NFPA 70 Article 517’s main purpose is to define the ways systems are installed to achieve NFPA 99’s defined level of performance. They are actually designed to complement each other with a distinction between installation and performance. However, it is hard to cover one topic without the other, which is why there is so much overlap between the two codes. It can become a bit overwhelming when you also include input from the other health care codes and standards, such as the Facility Guidelines Institute and various state-specific department of health services codes. However, it is the job of an electrical engineer to know these codes and how to apply them. Having an understanding of the intent behind each applicable code is what enables an electrical engineer to design the safest and most reliable systems. The design should meet or exceed all required codes and should also take into account the individual needs of the particular health care facility.

Risk-assessment changes

As previously mentioned, NFPA 99-2012 introduced the concept of a required risk assessment to assign a category level to the electrical systems within a facility. In 2015, the code further clarifies the requirements of the risk assessment. This edition adds section 4.2, which doesn’t require a risk assessment when all Category 1 requirements are followed.

According to the 2015 NFPA 99 Handbook, "The reasoning is that if the highest level of safety prescribed by this code is provided in a facility, then there is no need to conduct a risk assessment." This means that if it is feasible to design your electrical systems to comply with all Type 1 essential electrical system (EES) and Category 1 requirements, then you can bypass the risk assessment. However, if your systems (or budget) cannot be designed to the highest level even for areas or spaces that officially could be classified in a lower category level, then a risk assessment must still be performed.

Chapter 6, electrical systems

There are several areas in which NFPA 99-2015 includes redefined or reworded sections to closer align to the way that NEC 2014 is written. Probably the largest global change across the code is the replacement of patient care "room" with "space." This revised term has two distinct impacts. First, it reflects a change that was made in NFPA 70-2014 so the two have now adopted the same language. Second, this section now allows a single large room to be broken into several smaller "spaces" and thereby treated differently.

For instance, in a large room, there may be more than one different service being provided in separate spaces, such as a labor and delivery room or trauma room. Now, there are subcategories under the definition of patient-care space including a Category 1 or Category 2 space, both of which can be simultaneously happening in the same room. This new wording further supports the risk-assessment mentality adopted by the code by requiring a closer examination of the risks to a patient based on the actual procedure that will be performed in any given portion of a room.

In addition to this, several other definitions have been updated in NFPA 99 and now are consistent with NFPA 70. These include ampacity, bathroom, ground-fault circuit interrupter (GFCI), and coordination. Although these may seem like trivial modifications, the change helps to make things less "interpretive" between jurisdictions and aids the engineer in knowing what to expect when working in several different localities.

The next revision encountered in the 2015 NFPA 99-2015 is under the "minimum quantity of receptacles required" for patient-care space in section (see Figure 1 for additional information on this requirement). The actual quantities have not changed, and both NFPA 70 and NFPA 99 now match, but the following verbiage was added to NFPA 99: "They shall be permitted to be of the locking or nonlocking type, single, duplex, or quadruplex type, or any combination of the three. All receptacles shall be listed hospital grade."

This modified language now coordinates with the language in NFPA 70-2014, Article 517. What currently does not match is the "spaces" or "areas." NFPA 70-2014 still defines the required quantities based on critical care or general care, whereas NFPA 99-2015 defines them by Category 1 or Category 2, respectively. However, both align with respect to the required quantities, so perhaps the 2017 edition of NFPA 70 will revise those definitions to align.

Other hot topics

There were several contentious sections in Chapter 6 in the 2012 edition of NFPA 99 that created quite a ruckus among industry professionals. The main ones were selective coordination, wet-procedure locations, and application to existing systems. These same hot topics remain largely unchanged in the 2015 version (despite several efforts to revoke them); however, some were expanded on for further clarification.

Regarding selective coordination, the 2015 edition remains unchanged. It requires overcurrent protective devices (OCPD) serving the EES be coordinated to 0.1 seconds and beyond. This differs from the requirements in NFPA 70 Article 700, which requires full selective coordination (meaning to 0.01 seconds and beyond). NFPA 99 relaxed this requirement and it maintains that, for health care applications, other factors must be considered in the selection of OCPDs, such as arc flash hazards, equipment damage, risk of fires, or extended outages, and that the 0.1-second minimum coordination threshold provides full OCPD coordination for the majority of fault conditions that occur.

The 2012 edition also defined an operating room as a "wet-procedure location" unless a risk assessment determines otherwise. It listed requirements for how to serve the power to these wet locations from either an isolated power supply system or GFCI protection. NFPA 99-2015 maintains this same language; however, it expands on additional requirements when GFCI protection is used in section The code now specifies that if you don’t use an isolated power supply system for an operating room and instead choose to use GFCI, each receptacle shall:

  • Be an individual GFCI device
  • Be individually protected by a single GFCI device (see Figure 2).

This adds in the vital requirement that if a GFCI trips, only one outlet is interrupted. Having the power interrupted to more than one outlet could result in the loss of power to multiple pieces of equipment, causing a serious risk to the patient.

Existing facilities

One of the goals of the 2012 edition was to identify how the code is applicable (and in what specific areas) to existing facilities. The 2015 edition continued with this requirement with only a slight modification. NFPA 99 Chapter 6 helps to identify common issues you are likely to encounter in an existing facility and covers how you are expected to address them. Table 1 outlines these requirements. The only change to this area for the 2015 edition is that it removes the requirement to test cord-and-plug devices and fixed electrical equipment every 6 months. All required testing is now based on installation and failure rather than at regular intervals.

EES types

Another change in the 2015 edition of NFPA 99 is that the term "emergency system" is no longer used to refer to the life safety and critical branches. Instead, these two branches, along with the equipment branch, are now part of the EES as described in In addition, there is a new section (also applicable to Type 2 systems under, which states, "For the purposes of this code, the provisions for emergency systems in Article 700 of NFPA 70, National Electrical Code, shall be applied only to the life safety branch system."

This was added to the 2015 edition to clarify the relationship between NFPA 99 and Article 700 of NFPA 70. It is intended that only the life safety branch of the essential electrical system comply with Article 700, not the critical and equipment branches. Details in NFPA 99 further modifies how Article 700 is applicable to the life safety branch, which includes exceptions for complying with capacity requirements, wiring for fire protection (1-hour-rated cabling versus 2-hour-rated cabling) and emergency lighting (battery backup), and selective coordination (NEC 700.27). This addition should clear up any confusion for inspectors or plans reviewers, who may be more familiar with Article 700 of the code than health care emergency systems, and help to bring some consistency in the review of the EES.

The other notable change to the EES requirements in the 2015 version is that it does not contain Section 6.6 "Essential Electrical System Requirements Type 3." There were previously performance requirements for Type 3 EES; however, the use of this type of system was never referenced elsewhere in the code. This meant that no spaces were required to be served from a Type 3 system, so the committee deleted it altogether for the 2015 edition.

Alternate sources of power

The final change in NFPA 99-2015 is the new verbiage in section The code now allows fuel cell systems as a permitted alternate source of power for all or part of an essential electrical system. A fuel cell converts the chemical energy of reactants (a fuel and oxidant) to usable energy via an electrochemical process (refer to figure 3). NFPA 99-2015 further details that when designing a fuel cell power system, all of the following are applicable:

  • The system must be installed and meet all the requirements of NFPA 853: Standard for Installation of Stationary Fuel Cell Power Systems.
  • There must be a fully redundant (N+1) unit.
  • The system still must conform to the Level 1 requirements of assuming and transferring all loads within 10 seconds of loss of normal power.
  • There must be a continuous source of fuel supply and the same quantity of onsite fuel storage as required for other alternate power sources.
  • A connection for a portable diesel generator is required of sufficient capacity to supply the life safety and critical branches.

These new provisions in the 2015 edition are included to allow the use of new technologies while still ensuring the same minimum level of safety. The hydrogen fuel cell is an emerging technology that combines the advantages of batteries and diesel generators and eliminates some of their disadvantages. Hydrogen fuel cells are quiet, produce no emissions (only heat and clean water), and require minimum maintenance.

However, fuel cell systems have some major limitations when used as a health care backup power supply that must be considered. One potential issue is a concern associated with the safety of handling and storage of hydrogen. Type 1 systems require anywhere from 24 to 96 hours of onsite fuel, so depending on the size of the EES, storage of that quantity of hydrogen may become a limitation.

In addition, another drawback is the difficulty a fuel cell system can present in assuming loads in 10 seconds. During start-up, hydrogen cannot be fed fast enough and the fuel stack tends to take more than 10 seconds to reach the required output power. This problem can be overcome by either running the system continuously or by adding a battery system to assist with start-up.

Probably the most limiting factor is power density. Currently, the largest fuel cell backup power supply system on the market is rated at 16 kW. Since many health care occupancies are designed with systems starting at 500 kW and range up to several-megawatt systems, introducing a fuel cell system to support the entire EES may not be feasible. It is certainly a consideration for portions of the system, however, to work toward net zero designs and assist in potential U.S. Green Building Council LEED certification points.

It is important for the design engineer to be familiar with all of the requirements in the code when designing health care facilities. There are additional electrical requirements peppered throughout the code, and Chapter 10 specifically addresses electrical equipment and some of the performance criteria and testing requirements related to electrical equipment. There also are requirements within the gas and vacuum systems (Chapter 5) and HVAC (Chapter 9) chapters. Having an understanding of each area is what enables an electrical engineer to design the safest and most reliable systems.

Danna Jensen is vice president at WSP + ccrd. Most of her work consists of designing electrical distribution for hospitals; she is the project manager of major hospital projects, which includes knowledge of all mechanical, electrical, plumbing (MEP), and fire protection systems as well as commissioning. She is a member of the Consulting-Specifying Engineer editorial advisory board.