Modeling the Future of Airport Security

The number of air travelers is rising each year, which poses capacity challenges for many airports in terms of performing passenger screening and maintaining the resources and space needed to manage potential security risks. To help airports better manage these risks while still enhancing the passenger experience, a research team led by Pacific Northwest National Laboratory (PNNL) developed the Aviation Security Screening Optimizer for Risk and Throughput (ASSORT) risk model. ASSORT’s methodology in assessing risk-based approaches for passenger screening and checkpoint operations was the focus of a paper recently published in the Journal of Transportation Security.

Speaking to the benefits of ASSORT, as outlined in the paper, PNNL’s Robert Brigantic, a chief operations research scientist and ASSORT principal investigator, said “Our model provides a means to quantify risk for different threat scenarios and then computes the overall risk to the checkpoint, aircraft, and airport by different traveler types. For airports, this could mean quicker and more accurate assessments of the trade-offs between the overall risk associated with checkpoints and the throughput rate of passengers screened.”

Sponsored by the Department of Homeland Security Science and Technology Directorate, the paper also highlights how ASSORT is being used to explore various aspects of checkpoint operations. This includes taking a novel look at conceptual traveler categories—general, trusted, and trusted-plus—along with tailoring different operating concepts to each traveler type at checkpoint screenings.

“For instance, travelers with a higher trust level may encounter fewer screening technologies, resulting in quicker processing times at the checkpoint,” said Brigantic.

Moreover, ASSORT allows airports to explore trade-offs between the costs of deploying specific resources (both equipment and personnel) and the resources’ contributions to both risk and throughput.

The current version of the ASSORT risk model and its associated algorithms are contained in a prototype model that quantifies various settings. Although the current ASSORT results are based on a static point in time, researchers are implementing event simulation to model every single passenger’s arrival to an airport, their traveler type, and their subsequent processing and queuing at checkpoints to assess risk dynamically as a function of time over the course of a day.

ASSORT aligns with PNNL’s decades-long history of delivering science and technology for aviation security, including its award-winning millimeter-wave technology. ASSORT is based on and extends PNNL’s Airport Risk Assessment Model risk formulation as well as its scoring guide, which applies definitions, scoring criteria, and methodologies from the Department of Homeland Security and the U.S. Coast Guard to the process of scoring risk parameters.

In addition to Brigantic, the research team included PNNL’s Jennifer Willis, Rachel Pulliam, Julianna Puccio, Kathryn Otte, Emily Bonus, Brenda Forland, Nick Betzsold, Atithi Bharth, Jonathan Mills, and Casey Perkins.