Everyone hopes that the current H1N1 2009 pandemic (swine flu) will remain mild, but the reality is that hospital providers must be prepared for unmitigated virus outbreak. In September 2009, doctors at Dell Children’s Medical Center in Austin, Texas, set up two tents, each capable of housing up to 16 beds, after being swamped with young patients over a weekend. The tents were erected just outside the Emergency Department (ED) entrance and were used to triage patients with less severe flu symptoms.

Federal guidelines allow jammed hospital emergency departments to set up alternate sites to screen influenza-like illness, stationing hospital personnel outside the ED to login and redirect patients seeking care. The need for alternate triage systems such as this requires careful planning and design, and must not be left to haphazard guesswork.

Architects and engineers must work together on the site plan for the area outside the building. Often architects are so focused on the interior design of the ED building, however, that the exterior site ends up being almost an afterthought, as they try to squeeze parking and an entrance drive into whatever space is left over. After the building is completed, beleaguered hospital facilities personnel may end up asking, “Where are we going to set up tents? How will we provide utility systems to them?”

The physical implementation plan

Directional air flow: Directional air flow always goes from “clean” to “dirty” areas—clean denotes those areas for patients who are diagnosed or physicians, staff, and employees of the hospital, and dirty denotes areas for undiagnosed patients, reception and triage, or holding. Directional air flow is the first line of contamination defense used in HVAC systems.

In today’s environment, architects, engineers, and hospital leaders must be proactive about figuring disaster planning into ED designs. Most hospitals have written standards listed in books and binders, but they may not have the physical implementation of the plan outlined as thoroughly as they should. If architects, engineers, and the hospital design team fail to take these measures, what is outside the ED can negatively affect what happens inside.

A key element of any ED design is the HVAC system including the airborne isolation infection rooms, which work in tandem to help prevent cross contamination. The HVAC system maintains negative pressures in “dirty areas” (areas where potential contaminants could be present), which forces the contaminants through directional flow outward and in the same direction. An airborne infection isolation room considered to be a “dirty area” draws air into the room and out through a dedicated hazardous exhaust system, thus preventing any contaminants from leaking back to uninfected areas.

Preparing for the worst case

In the case of H1N1 2009 pandemic, too many patients entering the hospital at the same time could overwhelm the ED, therefore, an alternate location for triage and treatment must be preplanned. If an alternate location is not available, contagious patients can overflow very quickly into other areas of the hospital, making a situation worse.

The hospital ED must also be designed to support mass contagion scenarios through the use of tents, mobile units, or temporary pavilions, and supplying these structures with power, oxygen, heating and cooling, and water and sewer allows for a sustainable operation until the “event” has been contained and the risks mitigated. The design team should identify the size and types of any tents, temporary structures, and mobile decontamination trucks that might be coming to the site, and work with engineers to plan how to connect utility systems to these tents and mobile units.

Hazard Vulnerability Analysis: The Joint Commission (TJC) standard for emergency management (EC.1.4) requires that a hospital response plan be based on a Hazard Vulnerability Analysis (HVA). The analysis is typically developed in the form of a matrix to determine the probability and the impact of a number of events, as well as the preparedness and risk to the hospital of these particular events. The HVA becomes extremely important when building an emergency response plan, because there are so many systems that might be disrupted within the engineering infrastructure.

Designers must thoroughly understand a hospital’s disaster plan. A hospital’s disaster plan is contained within a Hazard Vulnerability Analysis (HVA) and is typically a requirement for accreditation. To facilitate this understanding, hold additional design meetings spearheaded by the hospital’s safety officer. Designate space beyond the borders of the building as staging areas for large decontamination tents in the event of pandemics or mass casualties. Consider how ambulances and other emergency vehicles will access these areas.

Ultimately, the HVA assigns priority to the various events in order to determine those with the highest level of criticality. Those events ranking highest in criticality would be chosen for the highest emergency responsiveness. Thus, the HVA provides the basis for the design response when planning a hospital’s architectural and engineering infrastructure systems.

Among the first steps to take when preparing a hospital facility for a pandemic response is to perform an HVA, which identifies and prioritizes a hospital’s risks. The HVA is the foundation matrix for analyzing the key elements required to meet various situations. Mass contagion is typically part of the HVA. There may be additional risks for certain hospitals, such as a local railroad that poses a risk of chemical spill, or disasters such as hurricanes, where there is a potential for mass numbers of victims.

Computerized disaster response simulation

Our firm recently provided a client located just outside New York City with a computerized disaster response simulation that modeled what would happen if 200 patients showed up at the hospital within 60 minutes. Hospital personnel found it very useful to understand the impact to the overall facility when the whole triage function is relocated from within the ED to outside the building. As a result of this simulation, hospital design team members were able to quantify the numbers and types of patient locations, stretchers, and beds they would need in such a disaster. Simulations take away the guesswork. We believe that we are one of a small group of firms using this type of simulation modeling.

In ED design, you must first understand the demographics and the levels of acuity of the base population of patients that the facility will serve. Designers need to plan for both short-term surge capacity and mass emergencies or pandemics. The old-fashioned design standard of open, curtained cubicles between patients is a relic of the past, and today we have almost all private rooms in new ER designs, which helps to a certain extent to prevent airborne contamination.


H1N1 and emergency preparedness is serious business for hospitals, as is how regulatory agencies and healthcare institutions react to this threat of events. Because there are more potential calamities than available funds to prepare for them, determining how to spend these responsiveness dollars can affect our nation’s healthcare system. Portable and temporary solutions meet a hospital’s needs and provide a measure of control without requiring overinvestment within the facility, where mass contagion patients must not be allowed to congregate in large numbers.