File:HML+SNR+NRR hearing protection attenuation.jpg
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Summary
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Русский: Сравнение прогнозируемого и реального ослабления шума при применении вкладышей (берушей) из эластомерного материала EP100 (Willson Safety Products). По горизонтальной оси отложена разница между уровнями шума на рабочем месте, при их измерении с С-коррекцией, и с А-коррекцией (Lc-La). Эта разница возрастает, когда шум преимущественно низкочастотный, такой, от которого пассивные СИЗОС плохо защищают.
Вверху: Результаты, полученные при вычислениях с использованием результатов лабораторных сертификационных испытаний (средние значения и стандартные отклонения). Маркеры - вычисления для спектров "100 характерных шумов NIOSH"; графики - показатели ослабления шума NRR (США), SNR и HML (Европейский Союз и РФ). Прогноз на основе трёх чисел (HML) наиболее точно соответствует ослаблениям при защите от разных шумов. Внизу. Специалисты NIOSH провели измерения ослабления шума у рабочих на заводах [1]. Они определили средние ослабления шума и стандартные отклонения. Нижние графики точно соответствуют верхним, но использованы не результаты лабораторных измерений (средние значения минус стандартные отклонения), а средние ослабления шума, без вычитания стандартных отклонений, измеренные у рабочих. Аналогичное сравнение опубликовано в таблице в приложении C [2]. Методы вычислений и исходные данные: SNR, HML - ISO 4869-2:218 (ГОСТ ISO 4869-2-2022) NRR - Environmental Protection Agency (1979). 40 CFR Part 211 — Product Noise Labeling. Subpart B — Hearing Protective Devices. 44 Federal Register 56139-47. Спектры "100 шумов NIOSH " - William J. Murphy, Trevor W. Jerome, Hilary L. Gallagher*, Melissa A. Theis* and Richard L. McKinley. Comparison of Three Noise Reduction Rating Calculators for Passive an Active Hearing Protection Devices. EPHB Report No. 360-13a, July 2015 https://www.cdc.gov/niosh/surveyreports/allreports.html 1. Edwards, R. G., Hauser, W. P., Moiseev, N. A., Broderson, A. B., and Green, W. W. (1978). Effectiveness of Earplugs as Worn in the Workplace. Sound and Vibration 12(1), 12-22. 2. Appendix C. Real World Data (page 33). In: John R. Franks, Christa L. Themann & Cari Sheris. The NIOSH Compendium of Hearing Protective Devices (1994). DHHS (NIOSH) Publication No. 94-130, https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/PB95243200.xhtmlEnglish: Comparison of predicted and actual noise attenuation of EP100 elastomeric earplugs (Willson Safety Products). OX axis: the difference between the C- and A-weighted sound pressure level, Lc-La. The larger this value the larger is the low frequency content of the noises. Passive SPEs attenuate low-frequency noise worse than mid- and high-frequency noise.
Top: Results when laboratory data were used (mean attenuation values and standard deviations SD). Markers - calculations for "NIOSH 100 noises"; graphs - noise reduction ratings, NRR (USA), SNR & HML (European Union and RF). The prediction with HML most closely matches the attenuation of various noises. At the bottom. NIOSH conducted measurements of noise attenuation in factories [1]. They determined the average noise attenuation and standard deviations. The bottom markers and graphs correspond exactly to the top ones, but they are not derived from laboratory data (mean attenuations minus standard deviations). They are derived from the average noise attenuation (without subtracting standard deviations) of earplugs when used by workers in factories. A similar comparison is published in the table in Appendix C in [2]. Calculation methods and initial data: SNR, HML - ГОСТ ISO 4869-2-2022; ISO 4869-2:2018. NRR - Environmental Protection Agency (1979). 40 CFR Part 211 — Product Noise Labeling. Subpart B — Hearing Protective Devices. 44 Federal Register 56139-47. "100 NIOSH noises" - William J. Murphy, Trevor W. Jerome, Hilary L. Gallagher*, Melissa A. Theis* and Richard L. McKinley. Comparison of Three Noise Reduction Rating Calculators for Passive an Active Hearing Protection Devices. EPHB Report No. 360-13a, July 2015 https://www.cdc.gov/niosh/surveyreports/allreports.html 1. Edwards, R. G., Hauser, W. P., Moiseev, N. A., Broderson, A. B., and Green, W. W. (1978). Effectiveness of Earplugs as Worn in the Workplace. Sound and Vibration 12(1), 12-22. 2. Appendix C. Real World Data (page 33). In: John R. Franks, Christa L. Themann & Cari Sheris. The NIOSH Compendium of Hearing Protective Devices (1994). DHHS (NIOSH) Publication No. 94-130, https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/PB95243200.xhtml |
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| Source | Own work |
| Author | AlexChirkin |
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| current | 16:49, 25 October 2023 | | 938 × 1,012 (569 KB) | AlexChirkin | Uploaded own work with UploadWizard |
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