In vitro fertilization (IVF) is a booming industry, and with it comes a motive for new facilities. A major aspect of facility design is consideration for power, and, when labs or patients are involved, power quality. With embryos and patient safety at stake, proper backup power systems need to be designed and installed to ensure facilities are resilient enough to cease operations properly during a power outage. Without proper backup systems, both patient safety and embryos are at risk, and the facility is at risk of losing credibility and being liable for lost embryos or injured patients.

There are many complex space types present in these facilities, and the needs of each require careful attention. Standards beyond the National Electrical Code (NEC) come into play with how these systems are designed, so designers need to understand not only the systems required for all buildings but also those required for such complex buildings. Care must be given to the type of backup system selected, the loads placed on that backup system, and how power is distributed on those backup systems.

Space Analysis

When considering backup power solutions, specifically for IVF facilities, it is necessary to understand the various spaces present in a facility. Below is a breakdown of the types of spaces that are generally used along with a brief analysis of the consequences of a power failure in that space.

  • Hysterosalpingography (HSG) rooms are diagnostic rooms where dye is injected into the female patient and observed via X-ray to check for fallopian tube blockage. Typically, no anesthesia is involved, but, due to the nature of a needle being inserted into the patient, this space is generally considered a National Fire Protection Association (NFPA) 99 Category 2 space, which triggers code requirements for backup power.
  • Exam rooms in IVF facilities are generally used in the same manner as most other health care facilities. Patients are usually fully ambulatory, and not much more than a blood draw needle is involved. Power failure in exam rooms, while startling, are generally not going to cause any injury to patients. Facilities may prefer that backup power be available, but this is an operational consideration rather than a code concern.
  • Embryology labs, like most labs, very rarely allow patients inside. As such, there is virtually no chance of patient injury in the embryology lab. However, this area is where the magic of IVF truly happens. Within this space, there are hoods, micromanipulation tables, and incubators used for actual embryos. Because of this, a power loss knocking out the lights could cause an embryologist to inadvertently harm an embryo. Failure of incubators, refrigerators, and freezers can also cause embryos to perish, as they can no longer be maintained in a stable environment.
  • Cryogenic (cryo) storage is not a patient care space, but this is one of the few areas that actually has code-required power. In this space, embryos are stored for long durations under liquid nitrogen. Because of the high concentration of liquid nitrogen in the space, it can very easily boil off, filling the room with an atmosphere devoid of sufficient oxygen for human occupancy. Because nitrogen is a major component of air (78% is typical), a human adult typically cannot smell the lack of oxygen. But, without oxygen, humans will become hypoxic and may eventually lose consciousness. To prevent this, the space must be exhausted, and this fan must be placed on a backup power system. As this is code-required backup power (but not explicitly called out as “emergency”), this system falls under NEC 701. Additionally, monitoring systems are required to alert any occupants of a hypoxic atmosphere prior to entering, and these systems must be placed on backup power.
  • Endocrine andrology labs are “dirty” labs, unlike embryology labs. The word dirty is used not because the samples are contaminated but because the samples don’t need to be preserved after use. The lab is used for analysis of semen and blood samples to analyze hormone levels in a patient, which helps in determining potential causes of infertility. Unlike the actual IVF process, these samples are generally not time-sensitive, meaning another sample can be collected immediately if analysis of the first fails. As such, any backup power required for this space is purely an operational consideration, as a power failure will not impact patient safety nor will it pose an extreme hardship on the IVF process.
  • Collection rooms are used for patients to collect a semen sample for analysis. While a power failure may interrupt the collection process, this is generally no more harmful than a power failure inside a home. Although backup power may be desired for continued operation, this is by no means a critical area.
  • Transfer rooms are where the actual implantation of the embryo happens. Patients generally don’t need to be sedated, and the process normally lasts around five minutes. However, this is one of the few times an embryo is moved, and a failure of the lights could very easily startle a technician, causing the individual to damage a precious embryo. As such, backup power is essential here, not for code requirements but for operations.
  • Retrieval rooms are where eggs are extracted from a woman’s ovaries to be analyzed, frozen, stored, and/or fertilized. During the retrieval, the patient is generally anesthetized but not to the point where she is unable to walk 15 minutes after the procedure. However, the anesthesia typically causes this room to be considered a Category 2, as defined in NFPA 99. The exact implications of this are discussed elsewhere in this article, but this does bring about the need for code-required backup power.
  • Recovery rooms allow for recovery time, and any designer familiar with ambulatory surgery centers (ASCs) will be familiar with recovery bays. Built like a lighter version of a post anesthesia care unit (PACU), recovery bays in IVF facilities will be some of the lightest found in health care. However, as the patient will have just been anesthetized, these are still important spaces to ensure adequate power delivery to. These bays are typically equipped with a patient monitor to keep an eye on heart rate, blood pressure, pulse oximetry, etc., just as any other recovery bay. Even in a power failure, it is essential that these patient monitors continue working while a patient finishes waking up.

Those familiar with health care facilities, especially ASCs, will notice common room names, such as operating room and procedure room, are not on this list. While many facilities will tag their rooms with these more common names, these are merely simplifications of the other space types. Some facilities, for example, will refer to the room used for both hysteroscopy and retrievals as their procedure room or operating room. Some will use their transfer room also as an exam room. Ultimately, the room’s name does not dictate its needs; rather, its use dictates its needs. The most important part of designing any facility is to ask the right questions that will give the information needed to determine the space’s needs.

FIGURE 1: Duration is plotted horizontally, and frequency is plotted vertically. Infrequent and very short outages are not as significant as long outages or frequent outages. Consideration should be given to where a facility falls on this chart when selecting a backup power system. Image courtesy of New Ridge Engineering

Code Analysis

NFPA 99 Categories — Within any health care facility, IVF included, there are four code-defined categories of spaces. While there are many different space types, they ultimately all fit into one of the four categories below:

  • Category 1 Space — Space in which failure of equipment or a system is likely to cause major injury or death of patients, staff, or visitors;
  • Category 2 Space — Space in which failure of equipment or a system is likely to cause minor injury to patients, staff, or visitors;
  • Category 3 Space — Space in which failure of equipment or a system is not likely to cause injury to patients, staff, or visitors but can cause discomfort; and
  • Category 4 Space — Space in which failure of equipment or a system is not likely to have a physical impact on patient care.

At the end of the day, the category of space is what determines what kind of backup power system is required by code. Because of the nature of health care, there is no “this kind of space is always this category,” since Facility A might use its HSG room(s) only for scoping, but Facility B might use its HSG room(s) as a spare retrieval/procedure room. Ultimately, the facility’s governing body will have to decide what category each space falls into. However, based on some common uses, there are some common categories that fit spaces in IVF facilities:

  • Category 4 spaces: 
  1. Cryo storage;
  2. Endocrine andrology lab; and
  3. Embryology lab.
  • Category 3 spaces: 
    1. Exam rooms;
    2. Collection rooms.
  • Category 2 spaces: 
    1. Transfer rooms;
    2. Retrieval rooms;
    3. Recovery bays; and
    • Hysteroscopy/HSG.

    It should be noted that even though a space is not required by code to have backup power, that does not mean backup power is not paramount to the space. There are no requirements for backup power in the embryology lab, but a power failure would be detrimental to its operations, resulting in untold damage to embryos and equipment, financial losses for the facility, and the emotional toll associated with a patient losing an embryo. Even though backup power is not required by code, it may still be practically required.

    Requirements of Various Categories

    The code requirements of the categories are as follows:

    • Category 1 spaces must be served by a Type 1 essential electrical system (EES);
    • Category 2 spaces must be served by a Type 1 or Type 2 essential electrical system; and
    • Category 3 and Category 4 spaces are not required to be served by an EES.

    The major differences between Type 1 and a Type 2 EESs are that a Type 1 system consists of three branches (life safety, critical, and equipment), while a Type 2 EES only consists of two (life safety and equipment). Since the division of the branches occurs at the transfer switch, the biggest difference is that a Type 1 EES requires three transfer switches, while a Type 2 EES only requires two.

    In any case, the system is required to be an NFPA 110 Level 1, Type 10, Class X. This means the system must be rated to support life safety loads (Level 1), provide power within 10 seconds (Type 10), and provide power for a duration that is required by the application, code or user (Class X). Depending on the facility’s needs, the runtime may only be 90 minutes if procedures can be completed, embryos stored in cryo, and the facility evacuated. In this case, an inverter system may be a code-compliant solution to backup power. However, larger facilities may require longer to wrap up procedures and store embryos in cryo, which may necessitate a generator system. Any solution provided will have to be accepted by the local authority having jurisdiction (AHJ).

    Load Selection

    When designing most backup power systems, the cost to include an entire facility on the system quite often outweighs the benefits. As such, loads must be prioritized and selected for inclusion on the system.

    Lighting Loads

    Lighting should be included on the system in any area where continued operations are required for continued operation or safe cessation of operations. As with any facility (not only IVF facilities), egress lighting must be provided with an NEC 700 (emergency) backup power system. This can be accomplished either with batteries, a generator, or both. These loads are, out of any loads discussed here, most likely the least negotiable when considered for inclusion on the system.

    Additionally, lighting loads in any area where operations require orderly cessation (such as the embryology lab or transfer room), must be included on the backup power system. This allows anyone working in the area to see and wrap up their tasks, such as placing embryos into cryo storage or removing a needle from a patient.

    One area where generator systems tend to fall short is instantaneous power availability. Generators generally take just 10 seconds to provide power at the fixture, meaning the facility is entirely dark during this time. In any spaces where precise control is needed, such as the embryology lab or retrieval room, batteries should be provided to allow for continuous lighting, even in a power failure.

    Receptacle Loads

    Anywhere operations require orderly cessation, such as in the embryology lab or retrieval room, power is generally required. As such, receptacles should be selected in these areas for inclusion on the backup system. Within the embryology lab, this usually consists of the majority of receptacles, while in exam rooms, receptacles can generally be excluded.

    As with lighting, consideration should also be given to the time it takes to start the generator. Lab hoods and intracytoplasmic sperm injection (ICSI) tables quite often have computers associated with them as well as lighting for microscopes. Small uninterruptable power supply (UPS) systems (approximately 1 kW) can be provided to allow continued operation through the time it takes to start the generator.

    HVAC Systems

    A common issue of contention among facilities is the inclusion of the HVAC system on the backup power system. HVAC is undoubtedly the largest electrical load in any facility, and the high demands of an embryology lab in filtration, air changes, temperature, and humidity make this electrical load even larger. Many lab managers will ask (and several will demand) that the HVAC be included on the backup power system. However, a few considerations need to be given before undertaking this cost.

    1. How long is an embryo exposed to the ambient lab air?
    2. How reliable is the power in the area?
    3. Will the lab need to continue operating, even in a power failure?
    4. If the lab is shutting down, how long will it take the lab team to move all of its embryos into cryo storage?

    The answer to the first question is “not very long.” That said, it doesn’t take very long for an embryo exposed to volatile organic compounds to be neutralized. As such, air systems are designed to maintain strict air quality standards. Another consideration regarding air quality is how long it takes for air quality to diminish. A brief power failure will not cause an immediate spike in VOC levels. However, if the laboratory is to remain in use during a power outage, temperature and humidity levels can quickly and drastically change if the laboratory HVAC system is not on backup power due to the typically high heat loads within the IVF laboratory.

    Another consideration is how reliable power is within the area. If power has been continuously available for decades (as is often the case in major downtown areas), the expense of a highly resilient generator system may not be justifiable. When designing IVF facilities, especially in areas of high power quality, consideration must be given to both how often power outages occur and how long they last. In areas where power may reasonably be expected to fail for eight hours every few years, or in areas where power fails very often for one to two hours at a time, a more resilient backup system may be required than a major metropolitan downtown area. When selecting any backup power system, a major factor discussed must be how critical the mission is. In facilities such as hospitals and data centers, continued operation is essential to community safety, so resilient systems are essential. IVF facilities, however, are not critical in the same way hospitals are. However, there are both fiscal and personal considerations when shutting down a lab experiencing a power failure. It takes considerable time to move embryos into cryo storage, and during this time, patients cannot be seen. IVF is a very time-sensitive process, and rescheduling is quite often detrimental. There is often a window of no more than a few days where IVF can happen, and there are usually several months of hormone therapy being performed before those few days. If a clinic is expected to be nonoperational (for example, because of an incoming hurricane), sometimes arrangements will be made in another city as far as several hundred miles away for IVF to occur there. In response to this, some facilities consider themselves to be mission-critical, even if they don’t meet the typical definitions of it.

    When designing backup power systems for these facilities, a major concern of continued operation is that, if utility power is unavailable, failure of a generator will mean total failure of the operation. Once the generator is running, there is no additional backup power available. Tapbox systems that accept roll-up generators can alleviate this. By designing systems with the ability to connect a secondary backup generator, the maintenance costs associated with an additional permanent generator are negated, but the ability to have a resilient, continuously operating system persists.

    Another consideration when contemplating HVAC for backup power is how long it will take before embryos are entered into cryo. If the operations are small enough to accomplish this in two hours, air quality may not diminish enough to be detrimental. However, if the operations are large enough to require eight hours to store the clinic’s embryos, HVAC may be more important for inclusion.

    Figure 2: When considering backup power solutions, specifically for IVF facilities, it is necessary to understand the various spaces present in a facility. [megaflopp]/[iStock / Getty Images Plus] via Getty Images

    Backup Power Sources

    When selecting a backup power source, it must generally be am NFPA 110 Level 1, Type 10, Class X system. However, this can include various sources, including batteries and fuel-driven engines. These two are the most common, and considerations for both are discussed below.

    Diesel Generators — These are the most commonly used backup power systems because they are self-contained, can run for several days, and start very quickly. However, these systems require substantial maintenance and testing. These may be good fits for facilities in areas where power is likely to be lost regularly (at least once every two years), but the cost may not be beneficial for small facilities in major metropolitan downtown areas where power is very reliable. These may also be the only option allowed by an AHJ for an EES, so confirmation with the AHJ of their requirements must be considered during design.

    Natural Gas Generators — These systems have become more common in recent years. As they are driven by natural gas, which cannot be stored very practically, this still requires dependence on a utility. However, power failure occurs substantially more frequently in some areas than natural gas failure, and, often, the failure of both is associated with a major disaster. The use of natural gas generators reduces maintenance costs, and it eliminates the requirement to continuously bring fuel to the site in an outage event. Some AHJs do not accept natural gas generators where backup power is code-required, though, so coordination with the AHJ must be done during design.

    UPS (Battery) Systems — UPS systems require substantially less maintenance than fuel-driven generators, but they also offer substantially worse runtimes. Where a diesel generator may offer a 12-hour runtime, a UPS may require a footprint of several times that of an equivalent generator to accomplish that. The sweet spot for UPSs tends to be under two hours and very small loads. It's very rare that HVAC is able to be included on a UPS system without overdesigning, but UPSs are quite often sufficient to drive a small embryology lab, procedure room, and recovery bay for about two hours. This is often enough for a small clinic to wrap up operations and evacuate safely.
     When selecting the system, consideration should be given to two aspects of a power outage: frequency and duration. Frequent power outages that do not last more than a few seconds quite often do not lend themselves to the maintenance and cost associated a generator system that will barely have time to start before they’re useful. Similarly, infrequent but long outages do not lend themselves to battery systems where the batteries will be quickly depleted before the facility can cease operations.


    IVF facilities are complex, and they require careful design of backup power systems. Many different spaces exist, some of which are unique to IVF and not present in other health care facilities. There are procedures unique to IVF, and with those unique procedures come unique facility requirements. Loads must be carefully selected to ensure the system includes what is necessary but is not over-designed. The backup power source needs to consider both the loads served and the power conditions available from the utility. The most important aspect of designing these facilities is ensuring that the specific needs of the facility are met, considering both operations and systems.