Adjacencies: ED, OR, IR & Inpatient Transport

Where imaging sits in the building — relative to the Emergency Department, the surgical suite, interventional platforms, and the inpatient bed towers — determines turnaround time, patient safety during transport, and the operational cost of the department for its entire life. Imaging adjacency decisions are made at the master-planning and schematic-design stages, and they are among the hardest decisions to reverse once the modalities (with their shielding, structural slabs, and chilled-water plant) are installed.

Why adjacency is a clinical and capital decision, not a convenience

Diagnostic and interventional imaging is consumed by nearly every other service line, so its location is a hub-and-spoke problem rather than a self-contained department layout. Three forces pull on the floor plate:

Demand from acute departments. The ED, ICU, OR, and labor & delivery generate stat and time-critical imaging — a CT for suspected stroke, a portable chest film for a deteriorating ICU patient, intraoperative fluoroscopy. The shorter and more controlled the path between these departments and the relevant modality, the better the clinical outcome and the lower the transport burden.
Outpatient volume and throughput. Most imaging exams (routine MRI, CT, ultrasound, mammography, plain film) are outpatient and revenue-generating. These patients should never have to travel through clinical "back of house," and the department needs an outpatient front door that does not collide with inpatient/ED traffic.
Fixed-plant inertia. MRI magnets, CT gantries, and angiography systems are heavy, power-hungry, and shielded. Once a modality room is built — radiation shielding designed by a medical physicist, RF cage and magnetic shielding for MRI, structural reinforcement, dedicated power and cooling — relocating it is a capital project in its own right. Adjacency mistakes compound for decades.

Because of this inertia, adjacency is governed less by a single code clause and more by the operational model the owner commits to. The FGI Guidelines for Design and Construction establish the functional-program and space requirements that frame these decisions; the owner's clinical operations team, not the code, decides whether (for example) the ED gets its own dedicated CT.

The ED–CT adjacency: the single most important relationship

For most acute-care hospitals, the dominant imaging adjacency is between the Emergency Department and CT. ED patients drive a large share of stat CT volume (trauma pan-scans, stroke protocols, abdominal pain, chest pain), and minutes matter — particularly for stroke, where door-to-CT and door-to-needle times are quality-reported metrics.

Three common models, in increasing order of speed and cost:

Model	Description	Trade-off
Shared central CT	ED relies on the main radiology CT suite, reached via a controlled corridor.	Lowest capital cost; competes with outpatient/inpatient volume; longer, less-controlled transport.
ED-adjacent CT	A CT room located on the ED's boundary, dual-access — entered from inside the ED for stat cases and from radiology for scheduled cases.	Balances cost and speed; the workhorse solution for community and mid-size hospitals.
ED-dedicated CT	One or more scanners inside the ED footprint, controlled and staffed by the ED.	Fastest, supports trauma and stroke programs; highest capital and staffing cost; risk of under-utilization off-peak.

The dual-access ED-adjacent room is the most frequently specified compromise: a single CT serves both populations with a sliding/interlocked door arrangement and clear control-room sightlines into both corridors. EMTALA obligations reinforce this relationship — the medical screening exam for emergency patients frequently requires imaging, so the path from the ED treatment space to CT must be reliable and not dependent on outpatient scheduling.

Plain radiography (DR rooms) is typically embedded directly in the ED for the same reasons; many EDs also carry a portable/mobile X-ray unit and point-of-care ultrasound at the bedside. Trauma rooms are often pre-plumbed for overhead-tube or C-arm imaging.

The OR–imaging adjacency: intraoperative and hybrid platforms

The surgical relationship to imaging has two distinct perspectives: imaging brought to the OR, and imaging suites built as ORs.

Intraoperative imaging. Standard ORs use mobile C-arms (fluoroscopy) for orthopedic, spine, and vascular cases; some neurosurgery/spine ORs incorporate fixed intraoperative CT or, less commonly, intraoperative MRI (iMRI). iMRI imposes the full magnetic-safety regime (the four-zone model, ferromagnetic control, MR-conditional anesthesia and instruments) onto a surgical environment, which is a major design and operational undertaking.
Hybrid operating rooms. A hybrid OR is a surgical suite with a fixed, ceiling- or floor-mounted angiography system, used for structural heart (e.g., TAVR), complex endovascular, and combined open/endovascular procedures. The hybrid OR must satisfy OR-grade requirements simultaneously with imaging requirements — it is sized larger than a standard OR (commonly on the order of 700+ net square feet to accommodate the imaging gantry, anesthesia, perfusion, and surgical staff), carries OR air-change and pressure requirements per ASHRAE 170 and FGI, requires radiation shielding designed by a medical physicist, and needs structural support for the ceiling-mounted equipment and lead-lined control/equipment rooms.

Hybrid and interventional platforms are increasingly co-located in a procedural neighborhood with the cath lab, EP lab, and IR, sharing a common sterile core, prep/recovery bays, and control infrastructure rather than being scattered across the building. This clustering is one of the most consequential adjacency decisions in contemporary acute-care design.

Interventional Radiology and the procedural platform

Interventional radiology (IR) and angiography suites are procedural environments that blur the line between "imaging" and "surgery." Their adjacency requirements pull in two directions at once: