What does rubbing alcohol contain that kill sperms in hand?

You don't have to...: Any methods providing unfriendly environments such as tap water washing, quick drying, etc. will kill the sperms in dried-up semen on hands in considering high fastidious requirement for sperms to survive. Using rubbing alcohol is quick to kill by fast drying-up + denaturalizing semen but optional; yet, its smell may project a sense of safety and killing germs. More? Seek counseling.