Challenge: Hospitals, health care facilities
Neal Boothe, exp Global Inc., Maitland, Fla.
David W. Crossey, Principal/Vice President, Lovorn Engineering Assocs. LLC, Pittsburgh
Jeff Harris, PE, LEED AP, Director of Mechanical Engineering, HGA Architects and Engineers, Minneapolis
Michael McLaughlin, Senior Vice President, Southland Industries, Washington, D.C.
Michael Sheerin, PE, LEED AP BD+C, Principal, Director of Health Care Engineering, TLC Engineering for Architecture, Orlando, Fla.
CSE: What engineering challenges do hospitals and health care facilities pose that are different from other structures?
Neal Boothe: Among the most challenging aspects of hospital projects is insufficient capital for the best value design. It is easy to implement low-cost options, but in an environment of limited capital budgets, more expensive or comprehensive options often lack the support for funding. When determining mechanical, electrical, plumbing (MEP), and fire protection system design, accurate, reliable, and unbiased budgets must reflect first costs and total cost of ownership. Excess capacity should also be factored into initial budgets. Too often design teams value engineer extra capacity out of design to save on first costs. Total cost of ownership should include the ramifications of limiting or eliminating excess capacity.
David W. Crossey: HVAC systems must be designed to meet more stringent design requirements, such as minimum airflows in specialized rooms and strict requirements for humidity control. Hospital buildings must stay operational during construction, which results in a lot of preplanning to develop workable phasing plans. Medical gas piping systems, nurse call, telemetry, and emergency power distribution are all additional systems that must be addressed when you’re designing a new or renovating an existing hospital.
Jeff Harris: Hospitals are high-energy-usage buildings with strict ventilation, filtration, pressurization, humidification, and temperature requirements that are in place 24 hours a day. These requirements are based on ASHRAE, NFPA, and state codes; requirements and standards; and specific needs and requirements for each individual hospital or health care organization. This means that each project has a unique set of design criteria and design solutions. Specifically, there are challenges dealing with airborne infectious isolation rooms and protective environment rooms in maintaining pressurization and in the location of diffusers and return grilles to maintain not only the correct pressure, but also the desired path of airflow from clean to less clean. Hospitals also are under tremendous pressure to reduce costs, which in turn translates into tension between the construction cost and the long-term energy and maintenance costs of the mechanical systems.
Michael McLaughlin: Health care facilities are patient centric, meaning all design elements of the building are driven to support a healing environment for the patient. These goals are much different than facilities that might support a work environment, manufacturing process, or product. As a patient-centric facility, the engineering challenges are focused on indoor air quality (IAQ), infection risk control, contamination control, room pressurization, and sound control. The engineer also must address energy efficiency, sustainability, and maintainability, while providing practical cost-effective solutions. Keep in mind these challenges change from project to project depending on the owner’s program, local climate, regional codes, regulations, and energy costs. Without a doubt, health care facilities offer greater engineering challenges than any other facility type.
CSE: What is the most challenging aspect of hospital projects?
Harris: Many hospital projects are remodeling projects, or additions to existing buildings, both of which have low floor-to-floor heights. Since hospitals also have higher ventilation requirements, with correspondingly larger duct systems, careful coordination and integration with the ceiling, structure, and other infrastructure (electrical, low voltage, piping, plumbing, medical gases) systems is required. Another challenging aspect of the design of infrastructure systems for remodeled hospitals is the need to keep the existing areas and systems operational throughout the construction period. This requires coordination between the design engineers and architects, along with the contractors and the hospital operations team.
McLaughlin: Hospital projects are unique given their oversight from authorities having jurisdiction (AHJ), input from owners, user groups, specialists, and contractors, as well as technical requirements from codes, standards, and best practices. Often these sources can conflict and/or limit the available options for achieving the challenges. The engineer is challenged not only to find the optimum solution that addresses all goals and objectives, but must also effectively communicate the benefits and features of the solution in such a way as to satisfy all constituents on the project. Often, the latter is more challenging than the actual design solution.
Crossey: I think it’s the planning required to maintain services or keep sections of the building functional while the renovations are being done.
CSE: How have the needs and characteristics of hospitals changed in recent years?
McLaughlin: Hospitals today are facing a number of challenges that have changed the needs and characteristics of hospitals, all of which pose new and existing opportunities for the engineer. Changes to the health care cost model are driving providers to explore alternative means of delivering health care in a cost-effective way. This has resulted in new and progressive architectural layouts that challenge existing codes, standards, and concepts. Improved medical science has increased patient survival rates, resulting in the need for more acute care space, such as intensive care units and specialty centers. Finally, health care technology continues to advance at a rapid pace, resulting in significant retrofits of existing hospitals to accommodate the space and increased demand on MEP and fire protection systems.
Crossey: A higher level of scrutiny and an increased awareness to maintaining humidity levels in various areas within the hospitals. In particular, operating rooms, which are required to maintain relative humidity of 30% to 60%, present an interesting challenge when the rooms are being maintained at lower temperatures than they were originally intended.
Harris: One recent trend is that projects, specifically remodeling projects, have become smaller and more focused on one particular department or procedure, as a result of less available capital. For MEP engineers, it is difficult to integrate the smaller footprint of the project with the changes needed for the mechanical and electrical systems, which tend to be distributed far away from the specific department or area.
CSE: Please describe a recent existing building project you’ve worked on—share challenges you encountered, how you solved them, and engineering aspects you’re especially proud of.
McLaughlin: Southland recently completed the design and construction of the new Walter Reed National Military Medical Center in Bethesda, Md. This project included the new construction of 710,000 sq ft of acute care and clinic and the renovation of 410,000 sq ft of the existing facility. The design-build team faced numerous challenges when working on this project that were overcome through a series of small victories. The sum of these victories was realized when the project was completed within the stipulated three-year timeframe while the existing facility remained fully functional. This was a true testament to the resolve and dedication of the team that overcame significant logistics, planning, and execution challenges with innovative and brilliant solutions.
Harris: An existing hospital patient tower of a hospital needed to be brought up to current standards for ventilation and medical gases, along with updating the finishes and changing from shared to private patient rooms. The existing building was under a tremendous negative pressure, and temperature problems ranked high on the list of patient dissatisfiers. The engineering solution included new air-handling units with increased outside air capacity, increased dehumidification capacity, a new temperature control system with direct patient access to the room thermostat, and an upgraded medical gas system with an increased number of outlets per room.
Michael Sheerin: We have been involved in a multiphase renovation at Doctor’s Hospital in Miami, Fla., and among the biggest design tools you can bring is patience. Phasing needs can sometimes change due to evolving clinical demands, and the detailing of temporary conditions is key for you as a designer to understand whether what you think can be done by the contractor really can be.
Crossey: We recently renovated a portion of the children’s intensive care and step-down suite at a hospital in West Virginia. The focus of the project was to provide three protected environment rooms that needed to provide a clean environment for the patient as well as space for the parents. The existing air systems were not adequate, so we had to find a location for a new unit, which ended up being a roof two stories above and several hundred feet away. Routing the new supply and return ductwork as well as bringing chilled water and steam to the unit was difficult and required multiple phases to complete the installation. We designed the protected environment rooms themselves to maintain positive air pressure between the room and a common anteroom and then maintain a positive pressure between the anteroom and the main corridor.