Answer
The cause of David's hearing loss is damage to the hair cells in the inner ear. It is not conduction deafness but sensoneurial deafness
Damage to hair cells is caused by loud noise above 90 decibels( 90 dB) . This damage my happen quickly, as by a gun report or the blasting of a fire cracker. It may also develop slowly to some one who day after day listens to loud music or has to endure the sounds such as those that are made by electric tools or snowmobiles or motorbikes.
Work Step by Step
This kind of deafness is caused by loud noise above 90 decibels. It is sensoneurial rather than conduction deafness. It is caused by damage to hair cells in the cochlea. It may be temporary or permanent.
