{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T06:41:22Z","timestamp":1775198482491,"version":"3.50.1"},"reference-count":38,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2020,3,10]],"date-time":"2020-03-10T00:00:00Z","timestamp":1583798400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","award":["PTDC\/EEI-ROB\/28799\/2017"],"award-info":[{"award-number":["PTDC\/EEI-ROB\/28799\/2017"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Radiological monitoring is fundamental for compliance with radiological protection policies in the aftermath of radiological events, such as nuclear accidents, terrorism, and out-of-commission uranium mines. An effective strategy for radiation monitoring is to use radiation detectors coupled with Unmanned Aerial Vehicles (UAVs), enabling for quicker surveillance of large areas without involving the need of human presence in the target area. The main aim of this study was to formulate the parameters for a UAV flight strategy in preparation for future field measurements using Geiger\u2013Muller Counters (GMC) and Cadmium Zinc Telluride (CZT) spectrometers. As a proof of concept, the prepared flight strategy will be used to survey out-of-commission uranium mines in northern Portugal. Procedures to assure the calibration of the CZT and verification of the GMCs were conducted, as well as a sensitivity analysis of the sensors considering different acquisition times, distance to source, and detector response time. This article reports specific parameters, such as UAV distance to ground, time of exposition, speed, and the methodology to perform the identification and calculate the activity of possible radioactive sources. An effective flight strategy is also presented, aiming to use radiation detectors coupled with UAVs to undertake extensive monitoring of areas with enhanced levels of environmental radiation, which is of prime importance due to the lasting hazardous effects of enhanced environmental radiation in the nearby ecosystem and population.<\/jats:p>","DOI":"10.3390\/s20051538","type":"journal-article","created":{"date-parts":[[2020,3,10]],"date-time":"2020-03-10T11:59:36Z","timestamp":1583841576000},"page":"1538","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Performance Analysis of Geiger\u2013M\u00fcller and Cadmium Zinc Telluride Sensors Envisaging Airborne Radiological Monitoring in NORM Sites"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1014-908X","authenticated-orcid":false,"given":"Jorge","family":"Borbinha","sequence":"first","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7. 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4337-8519","authenticated-orcid":false,"given":"Yuriy","family":"Romanets","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7. 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2705-7077","authenticated-orcid":false,"given":"Pedro","family":"Teles","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7. 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0959-9382","authenticated-orcid":false,"given":"Jos\u00e9","family":"Corisco","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7. 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7186-2359","authenticated-orcid":false,"given":"Pedro","family":"Vaz","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10, ao km 139,7. 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2663-3514","authenticated-orcid":false,"given":"Diogo","family":"Carvalho","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0682-9621","authenticated-orcid":false,"given":"Yoeri","family":"Brouwer","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8949-0402","authenticated-orcid":false,"given":"Raul","family":"Lu\u00eds","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1997-5484","authenticated-orcid":false,"given":"Lu\u00eds","family":"Pinto","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3423-3905","authenticated-orcid":false,"given":"Alberto","family":"Vale","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5655-9562","authenticated-orcid":false,"given":"Rodrigo","family":"Ventura","sequence":"additional","affiliation":[{"name":"Institute for Systems and Robotics, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"given":"Bruno","family":"Areias","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9709-5231","authenticated-orcid":false,"given":"Andre B.","family":"Reis","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0670-1214","authenticated-orcid":false,"given":"Bruno","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"Instituto de Plasmas e Fus\u00e3o Nuclear, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,10]]},"reference":[{"key":"ref_1","unstructured":"International Atomic Energy Agency (2005). 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