A military hospital where evidence-based design supports patient-centered care
The new William Beaumont Army Medical Center is a 630,000-square foot hospital that will serve active-duty and retired U.S. military personnel and their families. The Army Corps of Engineers engaged HDR to design a state-of-the-art facility that meets the highest standards of sustainability and evidence-based design.
All hospitals exist to support the wellbeing of their patients. Today, health care leaders are increasingly aware of how hospital environments themselves--not just the surgeries or medications patients receive inside--affect patient outcomes. Evidence-based design (EBD) draws on research in numerous fields, from environmental psychology to workflow design, and uses these insights to optimize the design of health care facilities for patients, families and staff. HDR, an Omaha-based leader in EBD, set out to create a hospital at Fort Bliss that supported patient wellbeing in every way possible, whether patients were recovering from traumatic injuries or managing a chronic disease.
HDR came to us for specialized help with a number of engineering design issues, including ensuring good air quality and acoustics. The Fort Bliss site, located on a military base and near the El Paso International Airport, presented unique challenges on both fronts. We collaborated closely with HDR to develop a deep understanding of the project’s overall objectives, including those related to sustainability and EBD, and to develop air quality, noise, and vibration solutions optimized to support patient wellbeing.
Collaboration and communication were at the heart of our process with HDR. The Fort Bliss Replacement Hospital aimed to be a landmark in EBD, so we worked carefully to develop a detailed picture of HDR’s vision for the project and to ensure that every aspect of our work advanced that vision.
It was essential that everyone inside the hospital enjoy clean, fresh, odour-free air. So designers had to ensure that exhaust from all sources on the hospital campus moved safely away from fresh-air intakes in all weather conditions.
Our contribution to this outcome began with a design review to identify all sources of exhaust emissions that warranted detailed investigation. These included the hospital kitchen, emergency generators, atrium smoke exhausts, loading dock vehicles, ambulances, the research laboratory’s fume hood, and the central utility plant.
We then modeled how emissions might disperse across the hospital campus from these source sites. Wind tunnel modelling is widely accepted as the most accurate method of replicating airflow patterns around buildings and of quantifying the effects these patterns have on exhaust reentrainment (exhaust reentering buildings after being expelled). We built a 1:300 scale model of the proposed development and its surroundings, and used tracer gas to gain a detailed understanding of how exhaust would behave there. This comprehensive wind tunnel study allowed us to provide rich information to designers, including guidance on how to mitigate reentrainment risks both in normal conditions and during unusual weather events.
Acoustics, Noise and Vibration
All buildings have acoustics and vibration issues. The Fort Bliss Replacement Hospital faced a unique set of challenges arising from the combination of patients’ particular need for privacy and comfort, the hospital’s operational needs, and noise and vibration from nearby land use, including a military base and a civilian airport. We worked with HDR to ensure that our work reflected the best evidence about the role of noise control in patient-centered healing environments. We faced two key imperatives:
First and foremost, we had to ensure patient comfort around the clock. Sources of noise and vibration that might undermine that comfort included:
- air traffic at El Paso International Airport;
- dual-rotor Chinook CH47 helicopters at the nearby military airfield;
- the hospital’s own helipad;
- vehicle traffic on nearby Highway 375;
- the operation of the central utility plant on the hospital campus;
- equipment inside the hospital, such as the MRI machine;
- footfalls and other noise from hospital occupants, including staff.
A second critical goal was to ensure that sensitive hospital functions, including the operation of diagnostic imaging equipment, the delivery of particle therapy, and the use of operating rooms was not disrupted by excessive vibration from mechanical equipment, foot traffic or exterior environmental sources.
We conducted on-site baseline measurements, and used the resulting data to inform detailed noise and vibration modeling for environmental sources (the airport, the highway, and so on). We developed detailed assessments of potential vibration from the hospital’s mechanical equipment. We also performed advanced footfall vibration analyses to quantify the resulting vibration frequencies and amplitudes in the flooring systems. This work produced intelligence that enabled us to provide:
- recommendations for façade design to limit noise transmission into sensitive spaces
- performance requirements for partitions surrounding the MRI room
- specific recommendations on construction details to limit disturbances from MRI noise
- guidance on vibration-isolator selection detailed recommendations for flooring systems to limit footfall impacts for vibration-sensitive spaces and equipment.
The Fort Bliss Replacement Hospital is scheduled to open in 2020 as a world-class health facility that support the wellbeing of U.S. military personnel and their families in innovative ways. The hospital will also contribute new insights and momentum to the growing field of evidence-based design, which has the potential to improve outcomes for patients around the world. We are proud that Fort Bliss patients and staff will benefit from the design adaptations made possible by our expertise and capabilities in air quality, noise, vibration, and acoustics.