Design That Meets Ebola At The Door
Courtesy Shepley Bulfinch
Mechanical ventilation is supplemented by natural ventilation. The unit is oriented so that prevailing winds pass from the unit’s green zone and through the red zone, where they are exhausted through a chimney and a louvered opening.
Courtesy Shepley Bulfinch
In the prototype, everyone entering the facility is screened with a temperature check on arrival. One-way circulation separates Ebola-symptomatic populations from those who are symptom-free.
Courtesy Shepley Bulfinch
The triage unit provides a gateway and secure entrance to the hospital campus, isolating infected populations prior to entry. Asymptomatic individuals proceed to their destination once they are cleared to do so.
Courtesy Shepley Bulfinch
Those arriving by car are screened at the secured vehicular entry (left), while those arriving on foot proceed up the ramp (center). Once patients are confirmed as being infected, they leave the isolation rooms through a screened walkway (center right) to the covered ambulance bay (right), where they will be taken to an off-site treatment facility.
Courtesy Shepley Bulfinch
Designed to accommodate natural ventilation, the angled roof of the triage unit also creates a distinctive visual identity for the entrance to the hospital campus.
The recent outbreak of Ebola in parts of West Africa put in focus the lack of a coherent strategy for addressing infectious disease outbreaks, as fear and confusion around the crisis resulted in many potentially preventable deaths.
Partners In Health (PIH) has been leading a coalition to combat outbreaks of Ebola in West Africa. As part of its effort, PIH asked Shepley Bulfinch to prepare a facilities assessment report to identify existing deficiencies and potential opportunities to improve patient outcomes at four hospitals in Liberia and Sierra Leone.
As a secondary goal that aligned with the infrastructure assessment, the firm identified short-term and mid-range renovations, additions, and upgrades to strengthen clinical care at each facility. From this, the design team developed a triage prototype that addresses issues of air flow, circulation, and the management of contaminated materials.
While developed with the population of West Africa in mind, essential aspects of the prototype unit offer examples that can inform infectious disease control and public health around the world.
The ground up
Before considering potential built solutions, it’s important to conduct an assessment of existing infrastructure. For this project, two architects joined with a construction manager, an electrical engineer, a logistics and clinical operations specialist, and an emergency department clinician to visit three existing hospitals, two in Sierra Leone and one in Liberia. The assessment team interviewed hospital administration, clinical staff, and key maintenance and security personnel to identify critical supply needs, water and electricity issues, patient volumes, and security concerns.
The team learned that the most critical items to evaluate were those needed to maintain a functional healthcare environment, especially during difficult and unforeseen crises: electrical service, water supply, waste management, communications, and security. It’s equally important to devise strategies for implementing supplemental or redundant infrastructure systems that will allow the facility to be self-sufficient for a period of time. These should include emergency generators, water storage tanks, water filtration, waste incinerators, and solar photovoltaic systems.
Often overlooked, a clear strategy for storm water management is critical in developing areas, too, as many resource-limited areas have instances of heavy rainfall and lack systems to manage that water. Developing a basic system of channels or drainage trenches is critical for maintaining clear access and minimizes breeding ground for bacteria and other pathogens.
Operationally, the assessment determined that a triage unit would be needed at the first point of entry to a hospital campus to manage the influx of patients in an orderly manner and allow for systematic medical screening. Security is often a concern in resource-limited settings, and it was particularly important to assure clinical and administrative staff that the facility was safe and manageable during times of crisis.
Establishing a clinical gateway to the hospital also offered a way to incorporate a security checkpoint to monitor and control facility-wide access. Ultimately, a triage building also provides a visible and recognizable entrance for the hospital.
As the assessment showed, there was no consistency to how and when patients arrived at the hospital gate. Patients typically travel for long distances, many on foot, and huddle at the front gate to enter. To resolve this in the prototype, a covered and protected queue lane was placed outside the hospital wall to accommodate those waiting to enter. Space markers on the path promote a safe distance between patients in order to minimize possible disease transmission or physical contact.
The prototype is designed to be built with concrete masonry block on a concrete foundation and a sloped standing seam metal roof—building materials that are the most durable, easy to work with, and readily available in the world. The universality of these materials ensured consistency in the quality of construction and the opportunity to employ local residents, who would be familiar with the materials, in the completion of the unit. Additionally, all windows are located to accommodate a six-foot sill to maintain patient privacy, while taking advantage of natural daylight and reducing the electrical lighting load.
The core of the building is segregated into red (contaminated) and green (infection-free) zones. Movement is organized so that medical staff moving from green to red zones must pass through a “donning” area for protective garments; those moving from red to green zones must pass through a changing area where they remove and secure potentially contaminated apparel for later incineration. The red zones and donning areas are intended to be cooled with mechanical air conditioning units; however, a combination of ceiling fans and strategically located UV lights may be used for minimal cooling if A/C is too costly or puts too much of a demand on the generator. The massing and materials are designed to support natural ventilation in addition to the mechanical systems. The building form, window locations, and ventilated screens help minimize transmission of airborne pathogens.
An inside look
As for how patients, staff, and materials move through the space, prescriptive circulation management is essential to infection control. The prototype design emphasizes early segregation of symptomatic populations and one-way flow of potentially contaminated materials and staff through the following efforts.
Screening. On arrival, all patients, visitors, and staff present themselves at a screening/temperature check station. This includes individuals arriving on foot or by vehicle, including ambulance. Those who are not Ebola symptomatic may proceed into the hospital campus. Everyone at this point must wash their hands using a dispenser that contains a 0.05 percent chlorine and water solution for infection control, per World Health Organization recommendations.
Some patients who may present similar symptoms to Ebola (fever, severe headache, muscle pain, weakness, stomach pain, diarrhea, vomiting, bleeding) or are suspected to have other potentially contagious diseases such as tuberculosis will be asked to enter one of the protective isolation rooms for observation and treatment.
Isolation rooms. Those who are Ebola symptomatic are immediately directed to one of the isolation rooms. To further minimize possible transmission, two types of isolation rooms were designed. Patients with severe vomiting, diarrhea, and hemorrhaging are placed in a “wet” Isolation room, which is designed to be scrubbed and disinfected with a more concentrated 5 percent chlorine solution. Each room contains two patient beds with a washable, fixed, 6-foot-high divider between them. Two toilet stalls open onto each room. These stalls are washable and have floor toilets for ease of cleaning and maintenance. A handwashing sink in the center wall is piped with the appropriate chlorine solution. If plumbing and a large storage tank are not available, chlorinated water jugs and buckets should be provided.
Non-infected patient movement. Patients sent to “red zone” isolation who are found not to be infected with Ebola leave that zone through the patient shower room, then through the patient changing area, and finally into a covered screened walkway leading to the hospital. This is a critical step in the process of disc
harging patients from isolation areas. Anyone who enters this area must be properly decontaminated.
Infected patient movement. Patients who are confirmed as having Ebola follow a dedicated pathway to an adjoining outdoor covered ambulance bay, where they will be transported to a dedicated Ebola treatment unit off-site.
Deceased patients. The bodies of deceased patients are moved to a holding room on the exterior of the building adjacent to a loading bay for removal. This room is secured, air-conditioned with filtered exhaust, and completely sealed for safety and containment. Its walls, floors, and ceilings are treated with a protective epoxy coating that holds up to intense scrubbing and disinfectant.
One-way staff circulation. Staff attending to potentially infected patients enter the donning room, which is large enough for two or three people, proceeding to either the dry or wet isolation room from the red zone passageway. Staff leaving the red zone will enter a doffing spray area, then a shower/changing room for decontamination, before exiting to the covered screened walkway.
Some key lessons from the assessment include the importance of developing and practicing consistent protocols and procedures for patient screening, employing a rapid response crisis team, providing airborne isolation and decontamination areas at triage or the building entrance, designing spaces that can function autonomously during times of limited power or moments of crisis, and developing mechanisms for early detection, communication, and education.
While the infectious disease triage model for PIH was developed for deployment in resource-limited settings in West Africa, essential elements of the prototype unit can inform infectious disease control in crisis conditions around the world, whether the threat of the spread of infectious disease is triggered by natural, political, or migratory forces.
Gerard Georges, Associate AIA, is a project manager at Shepley Bulfinch (Boston). He can be reached at firstname.lastname@example.org.