- Tytuł:
- Attenuation of Noise by Motorcycle Safety Helmets
- Autorzy:
-
Młyński, R.
Kozłowski, E.
Żera, J. - Powiązania:
- https://bibliotekanauki.pl/articles/89964.pdf
- Data publikacji:
- 2009
- Wydawca:
- Centralny Instytut Ochrony Pracy
- Tematy:
-
noise attenuation
measurements on subjects
motorcycle helmets
motorcyclist conditions of work - Opis:
- For workers such as police motorcyclists or couriers, traffic and engine noise reaching the ears is an important factor contributing to the overall condition of their work. This noise can be reduced with motorcycle helmets. In this study, insertion loss of motorcycle helmets was measured with the microphone-in-real-ear technique and sound attenuation with the real-ear-at-threshold method. Results for 3 Nolan helmets show essentially no protection against external noise in the frequency range <250 Hz. In the frequency range >500 Hz, attenuation increases linearly at a rate of 8–9 dB per octave, to ~30 dB at 8 kHz. Lack of attenuation in the low-frequency range may cause annoying effects. In addition, high attenuation in the high-frequency range may decrease intelligibility of speech signals for a rider in a helmet. Attenuation measured in this study does not take into account noise generated by turbulent wind around the helmet. Thus, the measured values of attenuation represent a motorcycle rider’s best conditions of hearing.
- Źródło:
-
International Journal of Occupational Safety and Ergonomics; 2009, 15, 3; 287-293
1080-3548 - Pojawia się w:
- International Journal of Occupational Safety and Ergonomics
- Dostawca treści:
- Biblioteka Nauki
Artykuł