75% alcohol is suitable for sterilization and can be used for sterilization, including skin disinfection, medical equipment disinfection, iodine deiodination, etc. This refers to normal skin disinfection, not wound disinfection. 95% alcohol is not suitable for sterilization, but it is often used as fuel for alcohol lamps and alcohol stoves in medical units, and is used for heating laboratory reagents or pharmaceutical preparations after ignition, as well as for temporary disinfection of small medical devices. Pure alcohol or water is not enough to denature the proteins in bacteria, only the concentration of 70%-75% alcohol can make the proteins in bacteria lose their physiological activity.