Beyond electrical codes for better healthcare
Codes protect public health, safety, and general welfare as they relate to the construction and occupancy of buildings and structures. For healthcare facilities, patient safety is the backbone of the codes. Within the healthcare field, Article 517 of the National Electrical Code (NEC) is the standard electrical code for patient safety.
Codes protect public health, safety, and general welfare as they relate to the construction and occupancy of buildings and structures. For healthcare facilities, patient safety is the backbone of the codes. Within the healthcare field, Article 517 of the National Electrical Code (NEC) is the standard electrical code for patient safety. While updated every three years, it can still lag behind the needs of the latest hospital care or situational needs.
Codes only specify the minimum acceptable level of safety; they do not have the flexibility to envision future needs or anything beyond the average safety requirements. In light of this, it is worth examining a few code minimums and some examples of “flexing” the code for the future.
When designing a hospital, electrical healthcare designers recommended to open the code book, find the code requirements, and use them on the plans, according to any guidelines. Achieving a design that reinforces the healthcare needs of an entire community is a complex process and revolves around the understandings of numerous “audiences.” It involves getting to know the facility and its mission within the community, the strategy of the hospital leadership, and the needs of patients and staff. It also involves communicating with the facilities staff to understand their maintenance methods.
Assuring care for every patient
One can analyze minimum code requirements versus design standards with an example as simple as receptacle design in patient rooms.
NEC Article 517.18 places a minimum requirement for the number of receptacles at each general care patient bed. The code minimum is two duplex receptacles, one normal and one emergency. But this is likely not adequate for today's highly electronic healthcare system. A typical patient room can have the following devices plugged in at the headwall: patient bed, nurse computer, patient computer/game, patient monitor, oto/ophthalmoscope, infusion pump, extremity compression device, patient refrigerator, clock, television, and portable X-ray. That's 13 different items that could be plugged in on the headwall.
Going beyond the minimum requirements is recommended. Consider providing four duplex critical power and two normal powered receptacles. And when laying these receptacles out in the room, some of these devices should be placed 42 in. above finished floor for easy access by nursing staff.
For critical care patient beds, the requirements are not much greater: The minimum is three duplex receptacles. There also is a requirement for one dedicated critical power circuit. As with the minimums for the general care bed, this number of outlets is likely inadequate to supply the following equipment that could be needed for the critical care patient: patient bed, nurse computer, patient computer, patient monitor, oto/ophthalmoscope, infusion pump (up to four), syringe pump, extremity compression device, patient refrigerator, clock, TV, ventilator, intra-aortic balloon pump, “dedicated parameter” monitor, procedure light, electro-surgical unit, dialysis machine with an associated portable reverse osmosis water unit, portable X-ray, portable C-arm, electro encephalogram machine, or ultrasound machine.
Again, we recommend going beyond the minimum code requirements. At least 13 duplex receptacles will fill a hospital's current patient headwall needs.
Reducing patient disruption
A reality of hospital design is that projects and maintenance can disrupt patient care in these 24/7 facilities. There are a number of electrical design alternatives above code minimum that can help reduce potential patient disruption.
A new code requirement in NEC 210.4 (A) and (B) has a distinct effect on hospital circuiting. The new code requires that all multi-wire circuits have a common means to disconnect the phase conductors via a multi-pole circuit breaker or a combination of single-pole circuit breakers using an approved tie handle. If circuit neutrals are shared between patient bed locations, it could cause disruption during maintenance or project work. A new design standard in electrical healthcare design is that emerging circuits should have dedicated neutrals for all patient care area receptacle circuits. This will allow performance of maintenance and modifications in one patient room without affecting other patients.
All receptacles in patient care areas are required by 517.18 (B) to be hospital-grade receptacles. A hospital-grade receptacle is manufactured to take much more abuse than a commercial receptacle and has a higher plug retention force. Because the entire hospital can become a patient care area in an emergency condition, electrical designers might want to consider using only hospital-grade receptacles throughout the hospital.
An automatic transfer switch (ATS) is required to connect an emergency power branch to either the normal service or the generator source. During emergency power system testing, the short power outage that occurs while transferring between sources can cause electronic equipment to reset or restart. This can be disruptive to patient care. Using an ATS design that has a closed transition transfer can eliminate the transfer “blip” when going between two active sources.
All ATS require scheduled maintenance. This can be difficult and disruptive to hospital operations. To avoid this disruption, specify ATS that have the bypass/isolation feature. This allows the automatic switch to be bypassed so that maintenance can be performed on the switch without affecting hospital operation.
Care insurance for a fully operational hospital
If healthcare facility administrators want the facility to remain fully operational following a natural disaster, cataclysmic accident, or a terrorist attack, here's the perfect situation in which to flex the minimums of the NEC. In preparing a facility for a multi-day extended outage, it is important to consider the areas where going beyond code minimums has a real affect on keeping a hospital fully operational. Issues like cooling, potential generator failure, and fuel supplies are areas that need thoughtful decisions. The accompanying chart indicates a list of design decisions that go beyond the code.
Codes are critically necessary in today's healthcare design. But they are not the end of the discussion—only the beginning. Understanding the hospital's mission and the manner in which they function will allow you as an engineer to know how to work together with the facility team to design a hospital that has patient safety and care at the center of the design and potentially help create a fully operational hospital even following a disaster.
Provide multiple generators to serve the emergency load with N+1 redundancy for the required loads.
Allows for rigorous testing and for required loads to remain in service in the event of a generator failure.
Three automatic transfer switches (ATS) for required branches of emergency power
Provide additional ATS on the critical and equipment branches.
Multiple equipment branch ATS allow the facility to control which systems have power in the event of decreased emergency power system output.
Normal and emergency power provided in the emergency department, operating room, critical care area, and imaging departments.
Use an additional critical branch as the code permits to serve critical care, diagnostic, operating suite, and emergency department loads that are typically fed by the normal power branch.
In order for these areas of a hospital to be fully operational during an outage, it is important that all of the loads are capable of being fed from the emergency power system. Using multiple critical branches makes this possible.
Provide 2 days of generator fuel.
Provide 4 to 5 days of fuel capacity on site.
In the vast majority of outages, refueling would be possible within a 5-day time frame.
No cooling on emergency power
Provide cooling on emergency power.
Without cooling, within hours some hospital service lines will have to be shutdown; after a day or two, patients would need to be evacuated. The fully operational hospital must have cooling on emergency power.
Stover is principal and electrical engineer with FreemanWhite, an A/E firm specializing in healthcare projects.
AT A GLANCE
Codes are critically necessary in today's healthcare design. But they are not the end of the discussion—only the beginning. Codes only specify the minimum acceptable level of safety, but this is not enough for the modern electronic healthcare facility. Achieving a design that reinforces the healthcare needs of an entire community is a complex process and revolves around the understandings of numerous “audiences.” It involves getting to know the facility and its mission.