Overview of developments in the description and assessment of high intensity impulse noise exposure

Peter Teague , James Conomos , Vasos Alexandrou

New Zealand Acoustics, 30(1), pp.24- 34 . (2017).

The precise description and assessment of high intensity impulse noise can be difficult due to the rapid onset-rates, short durations, very high peak noise levels (and overpressures) and the non-linear acoustic behaviour in the near-field of the source. Furthermore, determining the likely impact on hearing is limited by the current tools available for assessing the actual noise exposure/dose, auditory hazard risk and potential (irreversible) hearing damage. This paper provides insight to the recent developments in the measurement, prediction and assessment of impulsive noise exposure. Guidance is given on the relevant standards and guidelines, the range of measurement and prediction methods, impulse waveform pressure-time characteristics, relevant noise metrics/descriptors, models of impulsive noise exposure and hearing damage mechanisms. Recently developed electroacoustic hearing models are explored, including the Auditory Hazard Assessment Algorithm for Humans (AHAAH) and exposure metrics such as Auditory Risk Units (ARU). Other emerging influences and synergistic effects due to ototoxic substances, human vibration and extended work-shifts are investigated. Realworld examples and the mitigation of high intensity impulse noise are explored along with the need for further research and innovation.