Main Article Content
Objective: To evaluate the active ingredient of 70% Alcohol in two most common daily usage patterns after container
opening i.e. the long opening period without container lid closure and the short period opening with the lid opening twice a
Methods: 70 percent Alcohol was prepared in two common usages package sizes of 60 ml, and 250 ml, of our institution.
We evaluated the quantity of ethyl alcohol that is the active ingredient in 70% alcohol in two aforementioned conditions to
determine the time duration that the alcohol concentration remained greater than 60 percent in 60 ml, and 250 ml, package
size. The alcohol concentration was quantified by a gas chromatography method for 3 batches and 5 samples per batch.
Results: The ethyl alcohol concentrations of 60 ml, and 250 ml, packages of 70 percent alcohol declined to lower than 60
percent in 18 and 32 days respectively in the long opening period condition, whereas the short period opening condition
resulted in running out of volume in 24 and 49 days for 60 and 250 ml, package before the decline of the ethyl alcohol
concentration to lower than 60 percent.
Conclusion: We can be confident that the 70 percent alcohol in our institution package sizes of 60 ml, and 250 ml,
preserve their antiseptic properties for 18 and 32 days respectively when the lid is left open, whereas they maintain their
antiseptic properties until the package is finished in the twice daily usage condition. These finding should be introduced into
the practice guideline of the medical personnel and the patients.
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