Does Tap Water Rinse as Well as Purified Water?

Q. Does tap water rinse as well as purified water?

A. As far as detergency is concerned, tap water will rinse just as well as any purified water. Rinsing is a mass displacement mechanism and in itself does not depend on the purity of the rinse water.  The reason to be concerned with the purity of the rinse water is that whatever is in the rinse water can deposit on your surface/instrument/vessel, etc. when the water evaporates away during drying.

You do run the risk of water spots from calcium and magnesium deposits in the event that the tap water has a high mineral content (water hardness). This can be minimized by wiping instruments and surfaces dry, shaking them off to remove water droplets and/or using a cosolvent like alcohol that forms an azeotrope to evaporate the water off.  Thus reducing or possibly eliminating residual tap water contaminants (water spots). In either case, even if incidental water spots are formed, water spots generally would not cause sterilization failure.

In the case of medical instrument cleaning and/or where sterilization comes after cleaning, the primary concern would be anything that would interfere with the following sterilization step. Any reasonably clean tap water will rinse away the very free-rinsing Alconox, Inc. detergent/residue mixture left on the instrument from the cleaning process and would not leave a pathogen shielding film or residue that would inhibit the sterilization process.

In instances where chemical disinfection is being used without a further sterilization step, then it can be critical to use high purity water to rinse with. However, when rinsing is intermediate to a final sterilization step, there is greatly reduced risk of cleaning and sterilization failure due to the rinse water.

To request these or any Alconox, Inc. detergents for free, please complete the questionnaire at Get Sample. For more information about any one of our Alconox, Inc. detergents, consult the technical bulletin for each product. Or click here to access each of our detergent’s  Safety Data Sheets.

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