International Detection Equipment for Materials Out of Regulatory Control

Year
2022
Author(s)
Sanjoy Mukhopadhyay - Mission Support and Test Services, LLC., Inc.
Richard Maurer - Nevada National Security Site Remote Sensing Laboratory–Andrews
Abstract

Science and engineering staff at the Remote Sensing Laboratory–Andrews have developed a robust, agile, maneuverable, and easy-to-use field-deployable radiation detection system from various platforms (vehicle mounted, aerial platform) under the auspices of the Office of Nuclear Incident Policy and Cooperation to be distributed to international organizations in support of material control and accountability programs. It has been designed and built on a foundation of mobile and aerial detection experience that spans four decades. The system is dependable, standardized, authenticated, and based on state-of-the-art technologies in aerial detection, data processing, telemetry, and systems integration. Detection sensitivities and response times are sufficient to assess health and welfare impacts on population to the levels outlined in the nationally and internationally adopted protective action guides. The system is a thallium-doped sodium iodide scintillator-based system, and we call it the Spectral Advanced Radiological Computer System (SPARCS). There are two standard SPARCS configurations: SPARCS-A (Aerial) and SPARCS-M1 (Mobile). The SPARCS can be used for both mobile and aerial operations. The system consists of a detector pod, an acquisition and telemetry unit (ATU), and a laptop computer. The laptop is the main interface for the user. The ATU is attached to the detector pod and records geo-referenced spectra, count rates, and alarm levels. The U.S. Department of Energy, National Nuclear Security Administration’s Aerial Measuring System uses two standard platforms to deploy SPARCS. A fixed-wing aircraft covers a large area in a short time, but the measured ground deposition is grossly averaged over. Rotary wing aircrafts (helicopters) allow us to obtain much more granularity and resolution of the ground deposition because these aircrafts can be flown at much lower altitude and with much tighter line spacing. Typical survey speed using helicopters is 70 knots per hour, which makes every ground position for which data are collected about 120 feet apart. Flight lines are typically 250 feet apart. Helicopters typically fly at 150 feet above ground level, but in an urban area where the canopy is high, the altitude can be adjusted to 300 feet and constantly maintained.