In the third installment of the healthcare team’s hospital planning blog series, I’ll focus on planning an imaging department in a hospital. With that in mind, Design Collaborative’s mission – to improve people’s worlds – is the first thing our healthcare team would think about when we begin to design. To achieve our mission, we focus on how we can:
Reduce anxiety for patients, family, and staff
Increase accuracy of diagnosis
Provide safety for patients, public, and staff
Provide a healing environment
This diagram illustrates the key departments in a hospital, the primary and secondary relationships that each department has to each other, as well as key entry points for patients. Using this diagram, it’s easy to see how each department is positioned in relationship to others. For a typical imaging department, it is not located on exterior of the building near an entrance like an ED would be. An ideal imaging department is designed with at least one exterior wall for magnet replacement in the MRI room over the lifetime of the hospital. These departments are more secure to keep the public out due to safety reasons. For example, there is a potential for visitors of patients to walk into an imaging room and expose themselves to radiation or high magnetic fields. To avoid this, the imaging department is more secure and monitored. As much as possible, the imaging department should be located adjacent to the Emergency Department for efficient and immediate diagnostics for critical patient cases.
There are several types of imaging modalities – MRI, CT Scan, X-Ray, Ultrasound, PET Scan, and 3D Mammography. I’ll focus on MRI (Magnetic Resonance Imaging) requirements. Once a hospital decides which piece of equipment they will purchase, several entities are involved in planning the imaging space for the MRI suite.
The architect must work with the MRI vendor, the RF (Radio Frequency) Shield vendor, and the contractor to design and install the system. Safety zones are required to protect the public from unnecessarily exposing themselves to the high magnetic field. It is a requirement of the American College of Radiology to have four clearly defined safety zones. When a hospital hires an architect, they should help them establish the safety zones in the layout of their MRI suite.
MRI systems are highly sensitive to radio frequencies. The RF shield, which is essentially a 6-sided copper lined box around the room, protects the MRI system from exterior radio frequencies for clarity of scan. The footprint for the RF shield is set by the architect during the design process. We will confirm the design of the RF shield with the RF shield vendor to help establish where things penetrate the shield, like duct work, conduits, plumbing, and others.
The next thing a hospital needs to consider when designing an MRI suite is protecting the public from a high magnetic field. Architects work with MRI vendors to establish the precise location of the isocenter of the magnet. From there, they design protective provisions to keep the public away from the most dangerous magnetic fields. Imagine an invisible shield radiating out from the magnet’s isocenter. This is called the Gauss Field. From the isocenter to the 5-gauss line is dangerous for anyone wearing ferrous metal, or for any metal objects. Anything within the 5-gauss line that is metal will essentially become part of the magnet. To avoid this and keep everyone safe, architects intentionally design barriers to deter people from getting too close. Pacemakers, cell phones, and credit cards are several altered when inside the 5-gauss line.
Here are examples from projects we were not part of where people did not respect the magnet. These are examples of what happens when ferrous metal is brought too close to an MRI suite. If it’s not anchored, this will happen. In the event of an emergency quench, which is sudden loss of superconductivity in the magnet, a cryogen vent is required to be able to expel the super-cooled helium gas that the MRI uses. This might happen if there is an issue with the machine itself. This is only used under emergency situations where the magnet needed to be immediately shut down.
CT (Computed Tomography) Scan and X-Ray rooms are designed differently than MRI suites because they involve radiation instead of magnetic fields. Instead of an RF shield, CT Scans and X-Rays require lead-lined walls, floors, and ceilings. This prevents unintentional X-Rays from getting outside of the suite. Electrical engineers coordinate infrastructure for controls and power to equipment to ensure that it’s safely placed within the lead lining.
Rooms are also designed with the evolution of advancements, replacements, and upgrades in mind. Each of these spaces is designed with the patient in mind first. Procedures are typically stressful for the patient, but good designers do their best to humanize the experience through design. We try to make the rooms functionally beneficial for the staff so they can do their work efficiently and safely. Patient comfort is important to our design. We set the stage for a patient to feel at ease during their stay.
Megan Yoder Assoc. AIA
Associate, Graduate Architect