Family medical alcohol can not be applied after the expiration date of one year. Because alcohol is easy to have non-volatile, in 95% concentration of anhydrous ethanol volatility than 75% concentration of ethanol volatility is stronger, volatilization of alcohol after the effective bactericidal component of ethanol will reduce the number of alcohol, so with the expiration of the alcohol disinfection can not play a very good effect of extermination. Currently there are many types of alcohol for home use, there are bottles of liquid dosage, alcohol cotton cloth for home use, is a cotton gauze type of small piece of packaging, there are also medical alcohol cotton, it is recommended that airtight, protected from light storage.