Remote quasi-distributed ionising radiation monitoring in nuclear facilities
Mentor: Óscar Esteban Martínez
Phone: (+34) 918856691
University: Universidad de Alcalá
Partner Host Institution:
Keywords: gamma radiation monitoring, inorganic scintillator, polymer optical fiber

Remote quasi-distributed ionising radiation monitoring in nuclear facilities

The use of fiber optic sensors for the detection and monitoring of ionizing radiation has become quite popular in recent years, outstripping the classic sensors, both optical and electronic, due to a number of advantages such as small size and weight, multiplexing capabilities, immunity to electromagnetic interferences, stability, etc. These advantages have made them especially suitable in dosimetry and brachytherapy inside oncology areas in hospitals, nuclear waste containers and nuclear power plants facilities monitoring, sterilization and industrial applications, etc. A further interesting feature is their ability to be deployed over large areas, which permit monitor different locations simultaneously with easy handling systems. This feature makes these sensors especially suitable for environmental and border monitoring. A current choice when using optical fiber sensors is the use of fluorescence techniques, in which inorganic scintillators are used as transducers between ionizing radiation and visible one. Then, the visible light is gathered by an optical fiber and guided towards the optoelectronic detection device at some distance from the radiation source. This permits that only part of the system is exposed to irradiation and an easy replacement of the distal end can be done if needed. From the variety of scintillators that can be found in literature, the most used is based on a mixture of a ceramic inorganic scintillator (Gadolinium Oxysulfide, also known as GADOX, doped with rare earths), which covers a short length of fiber at the distal end of a PMMA fiber patchcord, being the fluorescence coupled to the fiber through its surface. This setup can be used for gamma-ray monitoring (the most important contribution to gamma activity in nuclear fuel is due to the 137Cs isotope) at radioprotection levels, and can be especially suitable for the environment protection against accidental leakage, in which a quick response to any incident involving a hazardous nuclear material must be supported by a reliable detection of its presence in a constrained area.

Departament: Electronics
Research Group: Photonic Engineering Group
More Information:
Relevants projects on the area: SINFOTON2-CM (Sensores e INstrumentación en tecnologías FOTONicas 2) ref. P2018/NMT-4326. Comunidad de Madrir 2019-2222. IP. Dr. Óscar Esteban Martínez
Relevants publications on the area: 1.- A.I. de Andrés, Ó. Esteban, M. Embid, ‘Improved extrinsic polymer optical fiber sensors for gamma-ray monitoring in radioprotection applications’, Journal of Optics and Laser Technology 93, 201-207, 2017.
2.- Ó. Esteban, A.I. de Andrés, ‘Dynamic gamma-ray monitoring at radioprotection levels with extrinsic polymer optical fiber sensors’, Sensors and Actuators: A. Physical 271, 83-87, 2018