Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers
The EN 1793-5 and EN 1793-6 standards have been in use for many years as a method for measuring the intrinsic characteristics of noise barriers installed along highways and railways. They require a sound source and a grid of microphones, to be placed near the barrier and in free field conditions, ac...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-08-01
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| Series: | Environments |
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| Online Access: | https://www.mdpi.com/2076-3298/10/8/139 |
| _version_ | 1797584827743993856 |
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| author | Paolo Guidorzi Massimo Garai |
| author_facet | Paolo Guidorzi Massimo Garai |
| author_sort | Paolo Guidorzi |
| collection | DOAJ |
| description | The EN 1793-5 and EN 1793-6 standards have been in use for many years as a method for measuring the intrinsic characteristics of noise barriers installed along highways and railways. They require a sound source and a grid of microphones, to be placed near the barrier and in free field conditions, according to predetermined distances. In principle, small errors in positioning the sound source and microphone grid may affect the results obtained. An international round-robin test was carried out in 2012 to evaluate the repeatability and reproducibility of the method, but until now no studies have been carried out to evaluate and compare the repeatability of laboratory versus in-place measurements performed with the same equipment and its variance when an imperfect positioning of sound source and microphones is taken into account. In the present work, multiple series of sound reflection index and sound insulation index measurements performed on noise barriers of the same kind installed in the laboratory or along a highway are presented. The measurements were repeated in different ways: (1) in the laboratory, leaving the source and microphones unmoved to assess the repeatability of the results and of the measurement system under controlled conditions; (2) in the laboratory, repositioning for each measurement the source and microphone grid to assess the robustness of the method under real conditions but in a controlled environment; (3) in situ, along a highway open to traffic, repositioning for each measurement the source and microphone grid to assess the repeatability of the method under real conditions in a critical environment. In both reflection index and sound insulation index measurements, the standard deviation on single-number ratings in all cases examined is well below the value presented in EN 1793-5 and EN 1793-6, which was obtained from statistical analysis of the international round-robin test performed a dozen years ago, suggesting that expert operators with state-of-the art equipment can achieve much better results now. |
| first_indexed | 2024-03-10T23:57:13Z |
| format | Article |
| id | doaj.art-5a8bbe404f9c44dfac78b2cca4d06b1e |
| institution | Directory Open Access Journal |
| issn | 2076-3298 |
| language | English |
| last_indexed | 2024-03-10T23:57:13Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Environments |
| spelling | doaj.art-5a8bbe404f9c44dfac78b2cca4d06b1e2023-11-19T01:00:52ZengMDPI AGEnvironments2076-32982023-08-0110813910.3390/environments10080139Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise BarriersPaolo Guidorzi0Massimo Garai1Department of Industrial Engineering, University of Bologna, 40136 Bologna, ItalyDepartment of Industrial Engineering, University of Bologna, 40136 Bologna, ItalyThe EN 1793-5 and EN 1793-6 standards have been in use for many years as a method for measuring the intrinsic characteristics of noise barriers installed along highways and railways. They require a sound source and a grid of microphones, to be placed near the barrier and in free field conditions, according to predetermined distances. In principle, small errors in positioning the sound source and microphone grid may affect the results obtained. An international round-robin test was carried out in 2012 to evaluate the repeatability and reproducibility of the method, but until now no studies have been carried out to evaluate and compare the repeatability of laboratory versus in-place measurements performed with the same equipment and its variance when an imperfect positioning of sound source and microphones is taken into account. In the present work, multiple series of sound reflection index and sound insulation index measurements performed on noise barriers of the same kind installed in the laboratory or along a highway are presented. The measurements were repeated in different ways: (1) in the laboratory, leaving the source and microphones unmoved to assess the repeatability of the results and of the measurement system under controlled conditions; (2) in the laboratory, repositioning for each measurement the source and microphone grid to assess the robustness of the method under real conditions but in a controlled environment; (3) in situ, along a highway open to traffic, repositioning for each measurement the source and microphone grid to assess the repeatability of the method under real conditions in a critical environment. In both reflection index and sound insulation index measurements, the standard deviation on single-number ratings in all cases examined is well below the value presented in EN 1793-5 and EN 1793-6, which was obtained from statistical analysis of the international round-robin test performed a dozen years ago, suggesting that expert operators with state-of-the art equipment can achieve much better results now.https://www.mdpi.com/2076-3298/10/8/139noise barrierAdrienne methodEN 1793-5EN 1793-6sound reflection indexsound insulation index |
| spellingShingle | Paolo Guidorzi Massimo Garai Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers Environments noise barrier Adrienne method EN 1793-5 EN 1793-6 sound reflection index sound insulation index |
| title | Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers |
| title_full | Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers |
| title_fullStr | Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers |
| title_full_unstemmed | Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers |
| title_short | Repeatability of the European Standardized Method for Measuring Sound Reflection and Sound Insulation of Noise Barriers |
| title_sort | repeatability of the european standardized method for measuring sound reflection and sound insulation of noise barriers |
| topic | noise barrier Adrienne method EN 1793-5 EN 1793-6 sound reflection index sound insulation index |
| url | https://www.mdpi.com/2076-3298/10/8/139 |
| work_keys_str_mv | AT paologuidorzi repeatabilityoftheeuropeanstandardizedmethodformeasuringsoundreflectionandsoundinsulationofnoisebarriers AT massimogarai repeatabilityoftheeuropeanstandardizedmethodformeasuringsoundreflectionandsoundinsulationofnoisebarriers |