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The AHAAH model estimates the auditory hazard of impulsive sounds by modelling their transmission using a one dimensional electroacoustic model of the outer, middle and inner ear. This wave motion analysis applies the [[Wentzel-Kramers-Brillouin approximation|Wentzel-Kramers-Brillouin (WKB) wave dynamics method]]. The motion of the stapes footplate is estimated and the WKB approximation is used to estimate basilar membrane motions assuming a linear cochlea network model. The output of the AHAAH model is auditory risk units (ARUs), which are related to summation of the upward displacements of the basilar membrane at 23 different locations. The ARU for any waveform will be reported as the maximum ARUs at any of the 23 locations. According to the developers, the recommended limit for daily occupational exposures is 200 ARUs, while any dose greater than 500 ARUs is predicted to produce permanent hearing loss.<ref name=":1" /><ref name=":9">{{Cite journal|last=De Paolis|first=Annalisa|last2=Bikson|first2=Marom|last3=Nelson|first3=Jeremy|last4=de Ru|first4=J. Alexander|last5=Packer|first5=Mark|last6=Cardoso|first6=Luis|date=June 2017|title=Analytical and numerical modeling of the hearing system: Advances towards the assessment of hearing damage|journal=Hearing Research|volume=349|pages=111–128|doi=10.1016/j.heares.2017.01.015|pmid=28161584|pmc=7000179}}</ref>
The AHAAH model consisted of a set of proven algorithms that accounted for a variety of exposure conditions that influenced the risk of a permanent threshold risk, such as noise attenuation caused by hearing protection devices and [[Acoustic reflex|reflexive middle ear muscle (MEM)]] contractions that occur before the onset of the stimulus being received that reduce the damage to the ear in preparation of the sound.<ref name=":8" /><ref name=":10">{{Cite journal|last=Amrein|first=Bruce|last2=Letowski|first2=Tomasz|date=January 2011|title=Predicting and ameliorating the effect of very intense sounds on the ear: The auditory hazard assessment algorithm for humans (AHAAH)|url=https://www.researchgate.net/publication/301511369|journal=NATO|volume=|pages=|id=RTO-MP-HFM-207|via=}}</ref> Unlike previous energy-based damage models, the AHAAH could also accurately predict the scope of the damage by analyzing the pressure-time dependence of the [[Sound
Depending on the presence of hearing protection devices, whether the sound came unexpectedly, and where the sound originated—whether in free field, at the ear canal entrance, or at the eardrum position—the AHAAH model could predict the displacements in the inner ear because it was conformal with the structure of the human ear.<ref name=":10" /> For free field, the model assumed that the sound arrived straight down the ear canal and calculated the pressure history at the eardrum, taking in the energy transferred to the [[stapes]] as input to the inner ear. For waves recorded at the ear canal entrance or at the eardrum, the model took into account the proper origin point of the sound in the circuit diagram. The displacement of the basilar membrane is calculated from the displacement of the stapes and the AHU is then determined by measuring the total displacement of the waves at 23 different locations on the [[organ of Corti]] in the inner ear.<ref>{{Cite web|url=https://arlinside.arl.army.mil/www/default.cfm?page=354|title=Functional description of the AHAAH mode|last=|first=|date=September 1, 2010|website=CCDC Army Research Laboratory|url-status=live|archive-url=|archive-date=|access-date=January 7, 2020}}</ref> The effect of the impulse sound can be displayed to create a visual representation of the damage process as it occurs.<ref name=":0" /><ref name=":1" />
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