err
I think you need to first establish the "ambient noise floor" (i.e. counting all the hairs first)
next, establish the hair/db ratio (simple division)
now you know how many hairs/db you'll have 'at risk'
can you spell b_a_l_d ?

MMMM...true as I have no access to a db meter I must derive an equation that eliminates that variable....AHAAAA...E=MC², where E= the acoustic energy in db, M= the numer of migrains complained about by my gf while in the vacinity of the device and C²= the square cm of baldness caused by said device. MWAHAHAHAHA.....Wile E. Coyote....SUUUPER GENIUS

EDIT: It has come to my atention that a time period must be assigned to E. Thussly E= the number of migrains my gf complains about over a period of 2 days...that should be >20.....hmm could it be that the noise eminating from said gf= the ambient noise floor?