  Noise induced hearing loss (NIHL) as one of major avoidable occupational
related health issues has been studied for decades. To assess NIHL, the
excitation pattern (EP) has been considered as one of mechanisms to estimate
movements of basilar membrane (BM) in cochlea. In this study, two auditory
filters, dual resonance nonlinear (DRNL) filter and rounded-exponential (ROEX)
filter, have been applied to create two EPs, referring as the velocity EP and
the loudness EP, respectively. Two noise hazard metrics are also proposed based
on the developed EPs to evaluate hazardous levels caused by different types of
noise. Moreover, Gaussian noise and pure-tone noise have been simulated to
evaluate performances of the developed EPs and noise metrics. The results show
that both developed EPs can reflect the responses of BM to different types of
noise. For Gaussian noise, there is a frequency shift between the velocity EP
and the loudness EP. For pure-tone noise, both EPs can reflect the frequencies
of input noise accurately. The results suggest that both EPs can be potentially
used for assessment of NIHL.
