Clinical diagnostic facilities house laboratories where  tests are performed on clinical samples and specimens to obtain information about the health of a patient to aid in diagnosis, treatment, and prevention of disease. These laboratories offer a variety of testing services and can vary in size and complexity, ranging from labs co-located in medical office buildings and hospitals to standalone high-volume, high-throughput academic medical center and commercial core labs.

Organic growth of clinical diagnostic laboratories to accommodate emergent analytical equipment or test assays often leads to functional challenges that must be addressed. This is especially true in labs where regulatory compliance, turnaround time, and cost per test are significant measures of success. If alterations to the laboratory environment and layout are not planned proactively, they can impact the processing of samples and specimens, resulting in inefficiencies in lab flows. This issue isn’t exclusive to decades-old spaces, either. Too often, new labs are designed based on specific equipment requirements or on a simplistic analysis of program and budget, rather than on the functional realities of workflows that should inform configurations.

Decisions should be made with an eye on prioritizing flows in the context of achieving regulatory conformance and Lean operations. For example, if the most important criterion is cost per test, planning for high-throughput sample and specimen flow and turnaround time will be paramount; if sample or specimen chain of custody and integrity are considered most important, separation of sample and specimen flow and waste streams will also inform lab planning configurations. Of course, both are of vital importance, which is what makes the design of these spaces so tricky. To make trade-offs effectively, design teams need to know the scope of the lab operation; the resulting flows of samples, lab staff, and materials; and the operational issues lab employees face every day. Taking these first steps to prioritize and understand these issues will work toward removing bottlenecks and process overlaps and ensuring operational efficiency and cost-effectiveness.

Depending on the lab’s setting, scale, and function, a clinical diagnostic testing lab often includes varying densities of automated equipment for sample accessioning, processing, and testing, along with manual labs that support lower-volume test assays. Labs will also require space for a freezer, refrigerator, tissue storage, and, potentially, conveyance equipment to support the storage of retained samples and specimens. Interviews with lab technicians and operators are extremely insightful to ensure that sufficient program space is provided and readily accessible.

Additionally, staff offices and support areas in or near the lab to support functions such as test results review, reading and release, specimen slide review, quality assurance, and assay-development functions also need to be considered. The program needs for lab support areas are informed by staff load, equipment needs, on-hand supplies, sample/specimen storage, and lab throughput. As good practice, the location of these functions and their interrelationship to the overall lab layout should be vetted during pre-design programming meetings with lab users where work streams are mapped out.

Quantifying the number and types of tests that will be performed in a lab will also go a long way toward determining the staffing/shift model and, therefore, the scale of the lab. In the case of an existing lab, the scale and square footage should be informed by analyzing the existing lab arrangement for space compression and/or underutilization, while space for new labs may be informed by industry benchmarks from peer facilities. High-volume tests such as electrolyte profiles, chemistry profiles, complete blood counts, urinalysis, and immunoassays can be performed on connected automated clinical laboratory equipment platforms, and, thus, lend themselves to a modular lab footprint. On the other hand, high-complexity assays as designated by the U.S. Food and Drug Administration—including cytology, immunohistochemistry, peripheral smears, and most molecular diagnostic tests—often require more space to accommodate pre- and post-sample and specimen testing and preparation activities, including more sophisticated equipment and increased staffing needs.

Understanding flow

Regardless of lab type, the testing process begins with the arrival of samples and specimens. In a patient care setting, materials sent from an emergency or surgery department, for example, might be delivered by a lab tech or courier, with the only lab design consideration being the location of the primary lab entrance and/or stat window drop-off. A clinical testing lab, meanwhile, will receive specimen shipments from physicians’ offices or airports, via multiple express delivery services. Therefore, the first flow that must be accommodated is vehicular. Facilities should set aside space to accommodate convenient vehicular-based drop-off, taking into consideration access routes, long- and short-term parking, and quantity and location of loading docks.

In addition to sample delivery, movement of kits, buffers, and reagents that are used to support analytical equipment test platforms; personal protective equipment; and on-hand lab support materials will be among the materials coming into the lab that need to be planned for. Additionally, multiple waste streams, including office, recyclable, nonhazardous lab, and red bag/biohazard, will account for the outbound flows. To minimize cross-contamination, ideally, materials and support streams won’t be commingled with incoming samples and specimens. Among the decisions that will need to be made are whether separate docks will be designated for specimens and non-specimens, or incoming and outgoing materials. Labs with limited space can configure docks with “swim lanes” painted on the floor, with each type of material staged in its own lane and then delivered separately to a specific lab.

The lab floor plate itself also raises multiple questions of priority with regard to the flows of samples, personnel, equipment, and waste. One approach is to map current flows within and between all functional areas to determine what makes the most sense operationally, prior to delineating possible floorplan arrangements that support those functional flows.

Strategic planning

As a lab plan comes into focus, there are three major considerations planners should address. For high-throughput, high-volume, rapid-turnaround lab assays, single-floor lab arrangements with expansive continuous modular space should be sought out. Operationally, this approach has several benefits including space to accommodate automated sample sorting, equipment lines, and retained sample stockyards.

Adjacencies should also be prioritized, to enhance Lean flow and to optimize the lab’s overall testing enterprise. If 70 percent of the samples are being processed using automated platforms, those functions should be placed as close to the incoming  docks, de-boxing equipment, sample receipt, and accessioning as possible. Optimizing adjacencies and workflows will create efficiencies in labor and increased throughput.

Finally, lab flows must be evaluated to ensure samples and specimens are tracked via a laboratory information system to enable and conform with chain of custody as well as the efficacy of sample and specimen results and findings. During the lab programming and design phases, it’s important to ensure barcodes on samples and specimens are scanned at each prep and analytical step in processing. Too often in large-scale lab operations, significant time is incurred tracking down misplaced items, causing unnecessary labor burden and delays in processing.

At both an enterprise and individual lab level, early program collaboration with lab staff to confirm and right-size lab program area and environmental and operational needs will result in a lab design with operational flows that enhance throughput, support regulatory conformance, and, most importantly, corroborate the efficacy of sample and specimen results. 

Paul Hansen is an architect and principal with Flad Architects (Madison, Wis.). He can be reached at