Alcohol is the most common skin disinfectant. Different concentrations of alcohol are made from high-concentration alcohol diluted with distilled water.

70%-75% alcohol is used for sterilization and disinfection. 50% alcohol is used for anti-decubitus. 20%-50% alcohol wipe bath is used for physical cooling of patients with high fever.

Why is 70%-75% alcohol for sterilization ?

Alcohol can penetrate into the bacteria and cause the proteins that make up the bacteria to solidify. Therefore, alcohol is used commonly as a disinfectant in medical and health.

When 95% pure alcohol is used for disinfection, the effect of protein coagulation is stronger, because the alcohol concentration is too high. When high-concentration alcohol is in contact with bacteria, it can solidify the surface of the bacteria quickly and form a thin film, which prevents the alcohol from continuing to penetrate into the bacteria. The inside bacteria cannot be killed completely.

When some bacteria encounter high concentration of alcohol, they will produce a protective reaction quickly, forming spores with a hard shell to resist the damage of alcohol. When the time is right, the cells in the membrane will be resurrected. Therefore, the use of concentrated alcohol can not achieve the purpose of disinfection.

70%-75% alcohol can enter the bacteria body smoothly and coagulate the proteins that make up the bacteria without forming a thin film, which can continue to penetrate into the inside of the alcohol,then can disinfect and sterilize it completely .

If the alcohol concentration is less than 70%, it will not kill the bacteria completely.

The strength of alcohol sterilization and disinfection capacity is related to its concentration directly . It is not too high and too low, so 70%-75% alcohol is right.

The alcohol is very volatile. Therefore, the disinfectant alcohol should be placed in a well-sealed bottle immediately after sealing and stored for future use.So as not to reduce the concentration due to volatilization and affect the sterilization effect.

In addition, alcohol is more irritating, and mucous membrane disinfection should be avoided.