The Centers for Disease Control and Prevention (CDC) reports that “on any given day, about one in 25 hospital patients has at least one health care-associated infection.” (

That might be the only introduction necessary for this discussion, really. We’ve been covering the topic for a few years now in our pages, thanks largely to columnist Howard McKew and more recently courtesy of Dr. Stephanie Taylor. As they would tell you, there’s still a long way to go.

In May, Harvard University hosted another symposium (, which brought together a multi-discipline group of experts who looked at how to continue and improve the attack on these infections with strategies addressing surface areas to HVAC systems and beyond. Several of the expert presenters who attended this year’s symposium agreed to answer a handful of questions about the problem and how it relates to mechanical engineering for this sector. Each professional was free to answer as few or as many questions as they wish. Here’s what they had to say.


Let’s start on a positive note. Can you mention one or two areas where the engineering/HVAC/health care community has made progress over the last 20 years with regard to system design, technology, and/or maintenance for the health care environment?


Traci Hanegan

Traci Hanegan, P.E., FASHRAE, LEED BD+C

There has been an improved capability to track microbes in the environment using polymerase chain reaction (PCR) screening and metagenomics, so we now have a better understanding of the challenges we are up against. Also, we’ve been able to eliminate elements of the HVAC system that have been found to cause harm — for example, the prohibition of lined ductwork. Improved control systems with faster response times and more accurate sensors have helped as well.


Damon Greeley

Damon Greeley, P.E., CEM

What is most exciting to me is the advancement of precision and affordability of technologies to detect and help monitor key indicators for health care workers, maintenance, and support staff to better understand, control, and maintain better indoor environments through building management systems (BMS).


Steven Friedman

Steven Friedman, P.E., HFDP, LEED AP

I believe there has been great progress made in the integration process among our end users (researchers/clinicians/doctors/operational staff) for the built environment. This is a clear case of “lessons learned” when it comes to initial design straight through to efficiencies of program space. Involvement of the end users at the inception of any health care design/build is of great value when learning about the operational efficiencies of space use. Of greater value in complex programs is that we typically spend monies on a “mock-up build” so that our end users can review, utilize, opine, and provide us feedback. In health care, there is no overtime or downtime, so inefficient use or placement of equipment has a domino effect of use from our patients to our staff, etc.


Howard McKew

Howard McKew, P.E.

Quite honestly, I don’t think the health care HVAC industry has changed significantly. There is a focus on continuously improving the HVAC designs to save energy, but if you look at the ASHRAE health care section in the 2015 Application Handbook, there is very little new info on infection control. I believe the equipment manufacturers are pushing the issue of human comfort, not just space criteria. But, if you think about it, the manufacturers are the ones that invest in research. Most consulting engineers do not carry funds for research, so taking on innovative research for the health care community [often falls on] manufacturers.

As far as maintenance, it’s still a “necessary evil,” with retrofits and new construction seldom carrying maintenance funds in the building program. O&M funds come out of a separate pocket so, even with a new addition, there may not be any additional maintenance personnel added to the staff to take care of the new square footage.


If you could wave a magic wand, what is the most common retrofit need you see in hospitals to address today’s challenges?


Kevin Van Den Wymelenberg, Ph.D.

Kevin Van Den Wymelenberg, Ph.D.

I still see so many surgery suites connected to surrounding zones that force excessive reheat due to low temperature delivery requirements in surgery suites. These should be zoned to avoid this reheat.


Stephanie Taylor, MD, M.Arch.

Stephanie Taylor, MD, M.Arch.

Humidify patient rooms to an rh of 40-60 percent, improve insulation to prevent condensation, make windows operable (unless you live in Beijing), and make all rooms single.



The most modern BMS systems that not only integrate all air, surface, and building water utility systems, but also interface with patient records (de-identified) and clinical systems so that data and analytics can be performed to correlate the indoor environment with outcomes.



For health care program retrofits in New York City, our biggest challenge is allocating proper code-mandated space square footage. As the codes have evolved (and under continuous maintenance), we are challenged to allocate minimum special clearances with updated patient and support care environments. Spatial expansions are a result of newer technologies and additional health care programs that have been developed over time, which create the need for floor space and power.



Get the humidifiers up and running again.


How would you describe the level of awareness/concern about HAIs among ownership in the health care industry today? If it’s growing, what do you perceive as driving that increase ... better data, legal consequences, regulatory/reimbursement consequences?



The current state is still very myopic, meaning many measures are taken after incidences or outbreaks have already occurred. Better data and building environmental information will provide insight to areas of risk that can be addressed proactively.



In my experience as a physician, we have known how serious HAIs are for decades — at least since I graduated from medical school in 1984. Unfortunately, in U.S. medicine, there is a powerful and pervasive culture that blames individual docs for iatrogenic diseases. This scapegoating has perpetuated secrecy and shame for physicians (and nurses, PAs, et al.) around any patient harm that occurs from treatment or hospitalization.

This secrecy actually has worsened since 2012, when the Center for Medicare and Medicaid (CMS) mandated that hospitals self-report their HAI rates. Facilities with the highest rates were then penalized. This is obviously a Catch-22 for hospitals and discourages openness for several reasons. Clearly, hospitals don’t want to incur financial penalties, so truly honest HAI reporting to public databases is pretty much nonexistent. And without reliable HAI metrics for a baseline, how does one know which infection prevention interventions really work?

Having presented this “doom and gloom” perspective, I do see progress with HAI reporting (and therefore managing) in some arenas. One such arena is in pediatric hospitals, where Medicare payments for older patients are not part of their revenue streams, and therefore these hospitals don’t report to CMS. While HAI databases from pediatric hospitals are not open to the public, at least they do exist.

Another good change for reducing HAIs is the formation of several organizations that are supportive to hospital physicians and other clinicians and which publish actionable strategies to move toward a culture of hospital-wide accountability rather than individual provider scapegoating. A couple of examples of these organizations are Leapfrog and the Institute for Healthcare Improvement.


Along those lines, what would help drive more aggressive changes in design and/or maintenance from the top down?



It has to be tied to revenue, which is at the forefront. The cost of HAIs has to be identified as a budget line item — i.e. not be placed into an “other cost” type category. In other words, it needs to be identified as an opportunity for savings of health care delivery.



More investigative reporting on how HAIs are kept hidden to avoid legal liability.



I’ve felt that having the mindset that some pieces of mechanical equipment are in fact infection control devices is a good place to start. It raises the expectation for a high level of attention along the entire equipment life span from design to installation, commissioning, operations, and inspections.



Remove government penalties from the infection control movement. Make anonymous patient outcome data available to researchers. Send hospital executives, building managers, architects, and patients who survived HAIs to wilderness survival programs, like Outward Bound, and make them talk to each other.


How well is the average facility mechanical engineering team equipped in terms of resources, knowledge, and/or staff to do what you would consider a proper job in their side of this equation?



I have seen it vary a lot between facilities and regions that I have worked in across the country. The majority want to do the right thing and strive for what’s best, but they haven’t had specialized training in infection control. I don’t think we have a problem with motivation. In some facilities, I have watched budgets and time pressures undermine some of the best efforts to do the right thing. There are so many hats to wear in that position, and the paperwork associated with heavy regulatory requirements can end up causing more harm than good.

We can’t give up. As our facilities grow in complexity, hospital facilities staff would benefit from more specialization within their field. We can provide deeper training on infection control to a few individuals and then allow them to focus on tasks related to that each day. How can we do right by the patients who depend on a healthy environment to heal in if the people responsible for operations are stretched so thin?



I think they are aware and have equipment to handle infection control (IC), but IC maintenance is distributed to numerous groups within a hospital, so there is no single-source point of responsibility and/or liability.



The average facility mechanical engineering team knows little about environmental control of patient infections, but then, the average hospital doctor knows even less.


In new construction, is there a recurring place in the design process where cost considerations typically hamper what would otherwise be a more effective design?



The design development phase is probably the most frequent place where this occurs.



I would have to say the No. 1 cause of cost implications that may hamper an effective design is the overlap of authorities having jurisdiction (AHJ). For example, in New York City, we follow the FGI guidelines, the New York State Hospital and Health Care Code, New York State Mechanical Code, and the New York City Mechanical Code. We also have state and local authorities, such as the New York State Department of Health, Pharmacopeia Regulators, New York City Department of Buildings, Fire Department of New York (FDNY), as well as local building inspectors. The point here is that there may be differences of opinion and interpretations of the various codes that make it difficult to build.



Always. Quite often, facility management isn’t even brought in on certain parts of the design process, and there are seldom funds in the building program to be spent on the annual IC costs. That comes out of another operating budget.



Yes, when it comes time to write the check, when someone wants to put in a decorative piece that takes up space or money, when the hospital leaders say, “HAIs? We don’t have HAIs,” and/or when the architect realizes that the design is way over budget and something has to be deleted.


Van Den Wymelenberg

Hospital design is incredibly complex and spans a range of specializations and time scales that make it difficult to achieve the precepts of the integrated design process. We have seen the integrated design process transform the approach to design, construction, and occupancy of other buildings types, but the specialized requirements and scale of many hospital projects make utilizing the integrated design process more challenging.

There is not one [specific] place in the design process where cost considerations hamper effective design. The integrated design process starts with the last facility in the health care system and extends to the next one beyond the current project. Cost is one of many critical factors that must be evaluated at every stage of design. Using the integrated design process is on one hand cliché, but on the other, it can be a transformative tool at each stage of the design, construction, and occupancy process.


Also on the design side, are there places in existing codes/standards that in your opinion should be updated, whether to combat HAIs specifically or for the general welfare of patients and staff?



Yes, definitely. There should be a minimum rh level of 40 percent in patient care spaces, including the patient rooms. High room air change (RAC) rates should be re-examined once the air is properly humidified (turn down RACs), and building envelopes should be designed and built/retrofitted to decrease thermal channels that allow condensation to occur in cold climates.

Please take this opportunity to offer a takeaway and/or discuss a point that is especially meaningful to you.


Van Den Wymelenberg

Evidence-based design approaches have shown us the value of daylight in health care facilities in terms of reduced patient length of stay and reliance on pharmaceuticals. And yet, many practical and health care related aspects of design make designing “well daylighted” hospitals and patient rooms difficult.

The line of sight to patients from nursing stations and corridors is an important quality of care component, as is the location of the toilet in each patient room (outside wall, common wall, or corridor wall). But these decisions also implicate the access to daylight and view for the recovering patient and the number of steps nurses must take to reach the bedside. This is a microcosm of the complexity of health care design.

What’s more, emerging research from the University of Oregon Biology and the Built Environment Center indicates that the exposure to different dosages and wavelengths of daylight has meaningful implications for the viability and diversity of indoor bacterial communities in indoor dust. In this respect, access to the outdoor environment — through daylight and views for the patients to wavelength and dosage regarding the effect on bacteria — can be considered an asset to support total patient health.



How can HVAC engineers be made to understand that their jobs in indoor air management have more impact on patient healing, and human health in general, than all of clinical medicine? Why is the control of indoor air parameters to support occupant health so ignored both by (most) physicians and engineers?



I think ante rooms should be mandatory for airborne infection isolation rooms. I like to ask people if they would sit and read a magazine if their chair were in the corridor outside of a tuberculosis patient’s room — and there wasn’t an ante room. My answer is, “Not a chance.”   



Traci Hanegan, P.E., FASHRAE, HFDP, LEED BD+C

Principal, Mechanical Engineer, Coffman Engineers

Traci Hanegan studied at the University of Idaho and is a principal at Coffman Engineers, Inc., where she leads the Mechanical Engineering Department and serves as secretary on the corporate board of directors. Her projects include a variety of biological containment labs, hospitals, zoos, data centers, and university facilities. Traci is an ASHRAE Fellow and is currently the chair of the ASHRAE Technical Committee for Laboratories, vice chair of the Technical Committee for Healthcare Facilities, and chair of the subcommittee on Infectious Diseases. She is an ASHRAE Certified Healthcare Facilities Design Professional and assisted in the re-writing of the ASHRAE Design Manual for Hospitals and Clinics, 2nd Ed.


Stephanie H Taylor, MD, MArch, FRSPH(UK), CABE

CEO of Taylor Healthcare Consulting Inc.

Dr. Taylor is an ASHRAE Distinguished Lecturer who graduated with honors from Harvard Medical School in 1984. She practiced clinical medicine and carried out academic research on cellular growth mechanisms for the next 20-plus years. During this time, she became very concerned about new infections that many hospital patients contracted while they were being treated for unrelated issues. Determined to better understand the connection to the hospital’s built environment and airborne infections and to find a practical solution to ensure better patient health care, she obtained her master’s degree in architecture from Norwich University. After several years working in an architecture firm focused on hospital design, she founded Taylor Healthcare Commissioning Inc., a nationally recognized consulting company that specializes in designing, building, and maintaining hospitals and other commercial buildings for optimal patient health and occupant safety.


Howard McKew, P.E., C.P.E.

President, Building Smart Software LLC

Howard McKew has more than 50 years of experience in building systems design, construction, commissioning, operation, and maintenance. The president of BuildingSmartSoftware LLC, he has been an industry leader in promoting the practice of commissioning and in developing commissioning standards, including serving as a contributing author to the AIA B291-2003 document outlining commissioning services. McKew is the author of more than 500 articles and monthly columns as well as a book, Managing People in the HVAC/R Industry. He is a contributing author to four McGraw Hill books and multiple ASHRAE Handbook chapters. In addition, McKew is featured as a guest author, speaker, and subject matter expert on several online webinars and podcasts, and he has also been the author of the “Tomorrow’s Environment” column in Engineered Systems since 1992 and “Back to Basics” since 1996.


Steven Friedman, P.E., HFDP, LEED AP

Director, Facilities Engineering

Memorial Sloan Kettering Cancer Center

Steven Friedman handles senior facilities management, spearheading the engineering department for facilities design + construction at Memorial Sloan Kettering Cancer Center. He brings more than 29 years of engineering and construction experience with a focus on implementing proper health care design standards to ensure patient safety and comfort. Mr. Friedman has designed systems for numerous world-class institutions throughout the Northeast and is the first New York state engineer certified as a Health Care Facility Design Professional, recognized by ASHRAE for his mastery of the technical knowledge covering design and operation of health care facilities.


Kevin Van Den Wymelenberg, PhD

Director Biology & Built Environment Center

Dr. Kevin Van Den Wymelenberg is an associate professor at the University of Oregon. He is the director of the energy studies in buildings laboratory and co-director of the Biology and the Built Environment Center in Eugene and Portland, Oregon. He has a Ph.D. in built environments from the University of Washington. His research areas include daylighting design, integrated design principles, energy performance, and air quality and the microbiome in buildings. Van Den Wymelenberg has consulted on several hundred new construction and major renovation projects with architects and engineers regarding energy efficiency and indoor environmental quality in buildings since 2000.


Damon Greeley, P.E., CEM, HFDP, CBCP, EDAC, CHFM

President of Global Health Systems Inc.

As the program director for Global Health’s research division, Damon Greeley investigates newer methodologies or technologies that improve infection control coupled with best life cycle costs. Greeley is LUMA Institute (LI)-trained and facilitates human-centered solutions that build consensus around the most advanced yet acceptable (MAYA) approach. He serves on the Center for Health Design’s EDAC advisory council and is charged with educating health care engineers on implementing evidence-based design. Additionally, he is actively engaged with his clients for infrastructure evaluation, planning, technical program management, and project implementation and commissioning services.

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