Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy
Infrared thermographs (IRTs) are commonly used during disease pandemics to screen individuals with elevated body temperature (EBT). To address the limited research on external factors affecting IRT accuracy, we conducted benchtop measurements and computer simulations with two IRTs, with or without a...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-09-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/23/18/8011 |
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| author | Siavash Mazdeyasna Pejman Ghassemi Quanzeng Wang |
| author_facet | Siavash Mazdeyasna Pejman Ghassemi Quanzeng Wang |
| author_sort | Siavash Mazdeyasna |
| collection | DOAJ |
| description | Infrared thermographs (IRTs) are commonly used during disease pandemics to screen individuals with elevated body temperature (EBT). To address the limited research on external factors affecting IRT accuracy, we conducted benchtop measurements and computer simulations with two IRTs, with or without an external temperature reference source (ETRS) for temperature compensation. The combination of an IRT and an ETRS forms a screening thermograph (ST). We investigated the effects of viewing angle (<i>θ</i>, 0–75°), ETRS set temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>E</mi><mi>T</mi><mi>R</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula>, 30–40 °C), ambient temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula>, 18–32 °C), relative humidity (RH, 15–80%), and working distance (<i>d</i>, 0.4–2.8 m). We discovered that STs exhibited higher accuracy compared to IRTs alone. Across the tested ranges of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula> and RH, both IRTs exhibited absolute measurement errors of less than 0.97 °C, while both STs maintained absolute measurement errors of less than 0.12 °C. The optimal <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>E</mi><mi>T</mi><mi>R</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula> for EBT detection was 36–37 °C. When <i>θ</i> was below 30°, the two STs underestimated calibration source (CS) temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>C</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula>) of less than 0.05 °C. The computer simulations showed absolute temperature differences of up to 0.28 °C and 0.04 °C between estimated and theoretical temperatures for IRTs and STs, respectively, considering <i>d</i> of 0.2–3.0 m, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula> of 15–35 °C, and RH of 5–95%. The results highlight the importance of precise calibration and environmental control for reliable temperature readings and suggest proper ranges for these factors, aiming to enhance current standard documents and best practice guidelines. These insights enhance our understanding of IRT performance and their sensitivity to various factors, thereby facilitating the development of best practices for accurate EBT measurement. |
| first_indexed | 2024-03-10T22:01:45Z |
| format | Article |
| id | doaj.art-c545809863304c148c0f38f5aff6dccf |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-10T22:01:45Z |
| publishDate | 2023-09-01 |
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| series | Sensors |
| spelling | doaj.art-c545809863304c148c0f38f5aff6dccf2023-11-19T12:57:24ZengMDPI AGSensors1424-82202023-09-012318801110.3390/s23188011Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting AccuracySiavash Mazdeyasna0Pejman Ghassemi1Quanzeng Wang2Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USACenter for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USACenter for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USAInfrared thermographs (IRTs) are commonly used during disease pandemics to screen individuals with elevated body temperature (EBT). To address the limited research on external factors affecting IRT accuracy, we conducted benchtop measurements and computer simulations with two IRTs, with or without an external temperature reference source (ETRS) for temperature compensation. The combination of an IRT and an ETRS forms a screening thermograph (ST). We investigated the effects of viewing angle (<i>θ</i>, 0–75°), ETRS set temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>E</mi><mi>T</mi><mi>R</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula>, 30–40 °C), ambient temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula>, 18–32 °C), relative humidity (RH, 15–80%), and working distance (<i>d</i>, 0.4–2.8 m). We discovered that STs exhibited higher accuracy compared to IRTs alone. Across the tested ranges of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula> and RH, both IRTs exhibited absolute measurement errors of less than 0.97 °C, while both STs maintained absolute measurement errors of less than 0.12 °C. The optimal <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>E</mi><mi>T</mi><mi>R</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula> for EBT detection was 36–37 °C. When <i>θ</i> was below 30°, the two STs underestimated calibration source (CS) temperature (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>C</mi><mi>S</mi></mrow></msub></mrow></semantics></math></inline-formula>) of less than 0.05 °C. The computer simulations showed absolute temperature differences of up to 0.28 °C and 0.04 °C between estimated and theoretical temperatures for IRTs and STs, respectively, considering <i>d</i> of 0.2–3.0 m, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>T</mi><mrow><mi>a</mi><mi>t</mi><mi>m</mi></mrow></msub></mrow></semantics></math></inline-formula> of 15–35 °C, and RH of 5–95%. The results highlight the importance of precise calibration and environmental control for reliable temperature readings and suggest proper ranges for these factors, aiming to enhance current standard documents and best practice guidelines. These insights enhance our understanding of IRT performance and their sensitivity to various factors, thereby facilitating the development of best practices for accurate EBT measurement.https://www.mdpi.com/1424-8220/23/18/8011elevated body temperatureinfrared thermographthermographyISO/TR 13154viewing angleexternal temperature reference source |
| spellingShingle | Siavash Mazdeyasna Pejman Ghassemi Quanzeng Wang Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy Sensors elevated body temperature infrared thermograph thermography ISO/TR 13154 viewing angle external temperature reference source |
| title | Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy |
| title_full | Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy |
| title_fullStr | Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy |
| title_full_unstemmed | Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy |
| title_short | Best Practices for Body Temperature Measurement with Infrared Thermography: External Factors Affecting Accuracy |
| title_sort | best practices for body temperature measurement with infrared thermography external factors affecting accuracy |
| topic | elevated body temperature infrared thermograph thermography ISO/TR 13154 viewing angle external temperature reference source |
| url | https://www.mdpi.com/1424-8220/23/18/8011 |
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