As travelers pass through border crossings, ports of call, and airport checkpoints, their safety is constantly being ensured by all sorts of screening technologies that have one critical goal: to identify and alert agents to potential threats. And, while these technologies do their jobs very effectively, it is important to keep asking questions like, “How can we ensure that our technologies continue to be universally and appropriately deployed where they are needed the most?”; “How can we be certain that they are always functioning optimally and safely?”; and “How can we make our screening processes more efficient and pleasant for travelers?”
To answer these questions, the DHS Science and Technology Directorate (S&T) has joined with the National Institute of Standards and Technology (NIST), the International Electrotechnical Commission’s (IEC) Security Inspection Systems Using Active Interrogation with Radiation working group and its Chinese and Russian National Committee partners, and other public and private stakeholders.
“Now, more than ever, it is essential that we research, develop, test, and implement international standards and criteria that will ensure the safety and effectiveness of the security screening systems that are employed both in the U.S. and abroad,” said S&T program manager Kai-Dee Chu. “Standards are just one of many critical tools that we can use to guarantee a safer and quicker experience for travelers as they transit through security checkpoints throughout the country.”
“International standards are universally agreed-upon criteria that government security agencies use to ensure that their screening technologies—airport checkpoint screening systems, luggage screening systems, portable x-ray scanners, etc., are adhering to industry best practices for both usage and safety,” explained Chu. “And the utilization and enforcement of these standards is how we will make sure that screening systems in the U.S. are conforming to these best practices and up to par with what our counterparts around the world are doing. Another benefit of having these standards in place is that they can, and should, be revisited, revised, and updated in real time, as security threats evolve and change and our technologies transform and improve to mitigate these threats.”
Recently, international standards development for technologies that detect liquids in luggage and carry-on items has become the focus of S&T, NIST, and the IEC’s working group and its Chinese and Russian National Committee partners. Currently, there are three standards that ensure the safety and effectiveness of these particular technologies: a Raman spectroscopy systems standard (IEC Standard 63085) for scanners that use non-ionizing radiation to identify liquids in transparent and semi-transparent containers; an X-ray computed tomography (CT) systems standard (IEC Standard 62945) for scanners that screen bottled and canned liquids without removing them from carry-on luggage; and a liquid CT systems standard (IEC Standard 62963) for scanners that produce cross-sectional images of scanned objects and other items in carry-on luggage to enable screeners to see inside them without having to open them or remove individual items.
“Liquid-screening technologies and standards are of particular interest to us right now, as they are increasingly being used in airports all over the world,” said Dr. Lawrence Hudson, a NIST physicist who is in charge of leading the IEC working group. “Thanks to these technologies and standards, many international travelers will no longer need to throw out their water bottles or bags of shampoo and lotion. Liquids may be screened separately for safety, or in some cases travelers can simply put their carry-on luggage into a scanner and walk through security checkpoints without additional delays. This will provide a more pleasant and speedy process for both our agents and the traveling public once we are able to widely implement these standards and technologies in the U.S.”
To facilitate the implementation of international liquid CT standards and technologies in the U.S., the IEC working group and its Chinese National Committee published an anticipatory standard titled “X-ray CT Inspection Systems of Bottled and Canned Liquids” in June 2020. Modeled after existing regulations that are already in place around the world, this standard describes the technical requirements for implementing liquid CT screening systems; criteria for the types of bottled and canned liquids, aerosols, and gels these systems need to be able to accurately detect; and safety requirements to ensure the safety of both the screeners and the general public.
“Since this standard is anticipatory, it is currently being reviewed by subject matter experts and our partners in the international community,” explained Chu. “We are also in the process of piloting liquid CT systems and standards in select airports around the country, such as Baltimore/Washington International Thurgood Marshall and Chicago O’Hare International, among others. Ultimately, we anticipate that these technologies will become a regular part of screening procedures at our airport checkpoints in the near future. Soon, you won’t have to worry about taking your water bottles or other liquid containers out of your carry-ons for separate inspection anymore.”
Dr. Hudson also noted that liquid CT systems have potential applications outside of the transportation security arena.
“These systems and standards already have a strong track record of performance internationally,” explained Hudson. “So, I wouldn’t be surprised if we eventually see them being used in other venues such as courthouses, sporting arenas, correctional facilities, and any other highly-trafficked areas where they could serve as a valuable security tool.”
Learn more about S&T’s international standards development efforts; for related media requests, please contact [email protected].