The Mission
A border crossing, a seaport, a stadium gate. These are the places where illicit nuclear or radiological material is most likely to move, and the places where it is hardest to find. The mission is interdiction: detect special nuclear material (SNM) and radiological sources in the flow of people, vehicles, and cargo, identify what triggered the alarm, and resolve it before the threat moves on. Officers need an answer in seconds, not a lab result an hour later.
Berkeley Nucleonics builds detection and identification instruments for exactly this work. Customs and border agents, port security teams, and event protection details use the SAM family of identifiers and personal detectors to screen traffic, run down alarms, and decide what to do next.
The Challenge
The hard part is not detecting radiation. The hard part is interpreting it. Naturally occurring radioactive material (NORM) is everywhere: kitty litter, ceramic tile, granite, fertilizer, bananas, and medical patients who have recently had a nuclear procedure all set off simple detectors. A screening line that stops every NORM source grinds to a halt and trains officers to ignore alarms. The instrument has to identify the isotope, recognize NORM for what it is, and reserve the operator's attention for the alarms that matter.
Two threats make the problem harder. SNM such as highly enriched uranium can be a weak gamma emitter, and a determined smuggler will shield a source with lead or steel to suppress its gamma signature. Neutron detection answers both. Neutrons pass through shielding that stops gammas, and a neutron count is a strong indicator of SNM. A border instrument that pairs gamma identification with neutron sensitivity sees what a gamma-only detector misses.
Scale is the third pressure. Screening a crowd, a rail yard, or a vehicle lane is a coverage problem, and no single form factor covers all of it. The answer is a layered posture: personal detectors on every officer, handheld identifiers for the alarm, and larger-area systems for crowds and vehicles.
Recommended Berkeley Nucleonics Solutions
Match the instrument to the layer of the screening posture.
Handheld identification
The SAM 940+ is the workhorse handheld radioisotope identifier for primary and secondary screening. It detects gamma and neutron radiation, identifies across the ANSI, SNM, IND, MED, NORM, and custom categories, and covers an energy range of 20 keV to 10 MeV with NaI, CeBr, or LBC detectors. When an alarm needs an identity, the 940+ provides it.
The SAM 950 is the ruggedized identifier for the harshest field conditions, with gamma and neutron detection and a choice of NaI, CeBr3, or LBC scintillators up to a 3 x 3 detector. Where teams want a modern, smartphone-linked interface, the delivers the same identification categories in a handheld that pairs to a phone for display and reachback.
Wide-area and crowd coverage
The SAMpack 120 (RD-120) is a human-portable backpack system for screening crowds, event venues, and large open areas on foot. It carries larger NaI, LaBr, or CeBr detectors than a handheld, detects gamma and neutron, and lets an officer walk a perimeter or a queue without revealing that screening is underway.
Vehicle screening
The SAMmobile 150 (RD-150) is a vehicle-mounted radiation detection system for mobile and lane screening. Its large NaI detectors and GPS mapping let a patrol vehicle or a fixed lane screen passing traffic and log where every reading was taken.
Personal detection for every officer
The Model 951 nukeALERT personal radiation detector gives each officer a pager-sized gamma alarm that runs all shift and signals the moment they walk into a field. For teams that need gamma and neutron in a personal device, the PM1703GNA-II MBT adds neutron sensitivity and dosimetry to the personal layer.
Why It Works
The posture works because each layer does one job well and hands the next layer a cleaner problem. Personal detectors on every officer turn the whole team into sensors, so a source moving through a checkpoint is likely to trip an alarm no matter which lane it takes. The SAMpack 120 and SAMmobile 150 extend that reach to crowds and traffic, where a handheld alone cannot keep up.
When an alarm fires, the SAM identifiers resolve it. Isotope identification across the ANSI, SNM, IND, MED, and NORM categories is what lets an officer clear a NORM nuisance alarm in seconds and escalate a genuine SNM signature instead. Neutron detection across the SAM line addresses the shielded-source problem directly, because neutrons reach the instrument when gammas have been attenuated.
The last piece is reachback. A field identification is a decision aid, not a verdict. The SAM instruments capture the full spectrum and the GPS-tagged context of an alarm, so an officer can forward the data to a remote reachback expert for adjudication before committing to a response. The field team detects and screens; the expert confirms; the chain of custody holds.
Getting Started
Berkeley Nucleonics can help you build a screening posture that fits your border crossing, port, or event, from personal detectors on every officer to vehicle and wide-area systems. Call 800-234-7858 or email info@berkeleynucleonics.com to talk through your concept of operations.
To compare models and detector options, see the Isotope ID & Radiation Detection documentation and selection guide.