Modeling Pre-Primary Non-Intrusive Inspection (NII) of Empty Commercial Vehicles
Status: Ongoing — Research Project
This project uses discrete event simulation modeling to analyze the effects of processing empty commercial vehicles through a non-intrusive inspection (NII) portal as a pre-primary strategy to improve commercial processing rates and increase security.
Model scenarios were focused on the southbound Pacific Highway port-of-entry (POE) staging area in Surrey, B.C.
Why This Project Was Needed
The US Customs and Border Protection’s (CBP) current interest in deploying a Z-portal NII for pre-primary scanning of trucks is specifically focused on empty trucks. At Pacific Highway, it is estimated that nearly a third of U.S.-bound trucks are empty. For empty trucks, inspection agencies are primarily interested in confirming that the vehicle is not carrying any cargo (or contraband) and that the driver is admissible to the country. If these conditions can be established prior to engagement with an inspector at the primary booth using technology that is faster than current inspection methods (i.e. NII instead of visual confirmation, facial recognition/RFID instead of verification at the booth) it is hypothesized that total inspection time for this large portion of arriving trucks would be significantly reduced.
By setting up a simulation model to reflect the current and proposed key process steps from a truck’s arrival at the end of the border queue to departure from primary inspection, the analysis can illuminate where introduction of new processes may affect (for better or worse) operations at other points in the system flow. This could lead stakeholders involved in this analysis to consider additional alternatives to model such as routing of FAST-program trucks, other locations for certain equipment (e.g. RFID or transponder readers), lane and booth allocation, etc.
Based on the available input data and assumptions, the outputs of this modeling exercise simulating the addition of an NII scanner to the staging area indicate:
a) Either minimal effects or reductions in wait-times for all trucks in the system if pre-inspection processing rates at the NII scanner are on average around 70 seconds or less and empty trucks are minimally impeded as they transit primary inspection
b) Increase in wait-times for all trucks, empty and FAST alike, if pre-inspection processing rates at the NII scanner are on average longer than 70 seconds, which causes extensive backups of empty trucks.
Additional operational issues that the model illuminates, are that 1) most NII scenarios show longer wait times for empty trucks than for loaded trucks and 2) the installation of the NII effectively removes the current wait-time reduction benefits for FAST trucks.
As implementation of the NII-for-empties concept is further evaluated by CBP and other U.S. and Canadian stakeholders, the current model outputs have quantified the impact of NII inspection time on overall system efficiency and also illuminated how re-ordering the sequence and physical location of process steps might create bottlenecks that would add to overall wait-time.