Request for information regarding high-resolution spectroscopic sensors

The Radiation and Nuclear Safety Authority of Finland (STUK) operates an extensive external radiation monitoring network (USVA) across Finland. The network comprises approximately 260 monitoring stations, of which nearly one-tenth are equipped with spectroscopic sensors in addition to standard dose-rate sensors. The current spectroscopic sensors utilize 1.5″ × 1.5″ LaBr₃ detectors coupled with photomultiplier tubes (PMTs) and tube-type multichannel analyzers (MCAs), all housed within aluminum weather shields. STUK plans to expand the spectroscopic subnetwork by roughly doubling the number of spectrometers and is seeking feedback and input from manufacturers regarding suitable instrumentation for this extension. No final decisions have yet been made on the technical specifications of the upgrade—such as the choice between PMT- and SiPM-based solutions—and STUK aims to gather information on the latest technological developments as well as relevant use cases involving different detector configurations. The existing USVA stations create some technical preferences: • To ensure backward compatibility with existing USVA stations, the sensor should support Power over Ethernet (PoE) for both power supply and control. STUK has tested solutions in which a separate single-board computer (SBC) is used as an interface between a non-PoE sensor and a USVA station. While such configuration may be considered acceptable, they are not preferred. • Sensor can be controlled via simple serial-like command framework due to limitations of the USVA station control computer. • USVA stations are serviced approximately once in 5 years. Sensor should be passively cooled and in general rugged. The primary purpose of the spectroscopic network is the identification of abnormal radionuclides during emergency situations. Consequently, emphasis is placed on energy resolution, with a value of <3.5% at 662 keV considered a rough target. However, solutions with lower resolution may also be considered, provided that detector sensitivity (crystal size) is significantly higher. Hybrid solutions combining a spectrometer and a dose-rate sensor are also acceptable. In such cases, the hybrid device is expected to meet the requirements for both spectroscopic performance and dose-rate measurement. For dose-rate functionality, the requirements are broadly aligned with IEC 60846-1, usage category Gwe, with a dose rate measurement range up to 1 Sv/h. STUK prefers the new sensor design to be as modular as possible, allowing subcomponents—such as the detector crystal, photomultiplier, and MCA/communication unit—to be user-serviceable and available as spare parts. Both fully field capable and laboratory grade solutions are acceptable.In the case of laboratory grade equipment, STUK will construct the necessary environmental shielding. STUK wishes replies to following questions: 1) Do supplier/manufacturer have options directly fulfilling most of the general requirements? 2) If supplier/manufacturer have a sensor the fulfills most but not the POE requirement, can the POE connectivity be added within reasonable timetable and cost? 3) Do supplier/manufacturer have experience regarding similar usage cases? Especially with other that NaI(Tl) or LaBr3 sensors. The request for information is answered under Other terms of the call for tenders. This request for information (RFI) is not a procurement notice or an invation to tender invitation. No economic compensation will be given for participating in this RFI. The publication of the RFI does not obligate the contracting entity to carry out the actual procurement. Responding to the RFI is not requirement for participation in any pontential future bidding competition. A procurement notice and invitation to tender may be published later.