20.500.12556/RUL-136093 Influence of atmosphere on calibration of radiation thermometers Current process of calibrating radiation thermometers, including thermal imagers, relies on measurement comparison with the temperature of a black body at a set distance. Over time, errors have been detected in calibrations of some radiation thermometers, which were correlated with moisture levels. In this study, effects of atmospheric air on thermal transmission were evaluated by the means of simulations using best available resources of the corresponding datasets. Sources of spectral transmissivity of air were listed, and transmissivity data was obtained from the HITRAN molecular absorption database. Transmissivity data of molecular species was compiled for usual atmospheric composition, including naturally occurring isotopologs. Final influence of spectral transmissivity was evaluated for spectral sensitivities of radiation thermometers in use, and total transmissivity and expected errors were presented for variable humidity and measured temperature. Results reveal that spectral range of measurements greatly influences susceptibility of instruments to atmospheric interference. In particular, great influence on measurements is evident for the high-temperature radiation pyrometer in the spectral range of 2–2.7 µm, which is in use in our laboratory as a traceable reference for high-temperature calibrations. Regarding the calibration process, a requirement arose for matching the humidity parameters during the temperature reference transfer to the lower tiers in the chain of traceability. Narrowing of the permitted range of humidity during the calibration, monitoring, and listing of atmospheric parameters in calibration certificates is necessary, for at least this thermometer and possibly for other thermometers as well. transmissivity of air radiation thermometer calibration measurement errors measurement uncertainty moisture humidity infrared thermometers transmisivnost zraka sevalni termometri kalibracija merilne napake merilna negotovost zračna vlaga infrardeči termometri true false true Angleški jezik Slovenski jezik Članek v reviji 2022-04-12 13:38:05 2022-04-12 13:38:07 2022-09-15 04:13:23 0000-00-00 00:00:00 2021 0 0 13 str. iss. 16, art. 5509 Vol. 21 Aug. 2021 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.317:536.51 1424-8220 10.3390/s21165509 74176771 RAZ_Mlacnik_Vid_2021.pdf RAZ_Mlacnik_Vid_2021.pdf 1 919A4CCB24188CCECDE29EDFDF7F076D 734a14d19fc52e62f4c8377b45d29d899547158e7ea536550593ab658f2af990 48b01f66-ba55-11ec-8aca-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=155554 https://www.mdpi.com/1424-8220/21/16/5509 1 f86cb222-ba54-11ec-8aca-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=155553 Fakulteta za elektrotehniko 0 0 0