Can hearing aids be claimed as a business expense?

I see that the 2018 business expense have changed where only certain occupations or situations can claim business expense with one of them being  "You're disabled and have impairment-related expenses". My father has profound hearing loss and in order to work he must pass a physical each year that includes hearing. He purchased two hearing aids about 4000$. I know I could include these in the Medical expenses, however, the 4000 is only half the amount that is needed for medical expense for it to effect the refund. So I was wondering about including it in the business expense. But from my understanding, if he uses them at work and personal life then it can not be claimed? Can anyone verify please?