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AOAC Use Dilution Test (AOAC 955.14; 955.15; 964.02)

The AOAC Use Dilution method is specified by US EPA as a primary method for substantiation of efficacy claims for disinfectants. It is particularly appropriate for dilutable disinfectants.

It is semi-quantitative, meaning that it relies on a series of 60 qualitative observations (a test tube changing from clear to cloudy as a result of microbial growth).

Recently, as the result of several years of work by industry members and EPA, AOAC lowered the performance standard for Staphylococcus aureus and Pseudomonas aeruginosa, making the test's pass/fail determination more reliable and - to the delight of disinfectant makers - making the test easier to pass.

Along with the change in performance standard, EPA added a requirement that the different required batches of test product be tested on different days.

Note: The information below is presented for educational purposes only. Current, detailed AOAC Methods can be obtained from AOAC.

Summary of Test Method and Important Parameters

Strengths of the AOAC Use-Dilution Test Method

Weaknesses of the Test Method

Antimicrobial Test Laboratories has put a great deal of time and thought into perfecting the way we execute the AOAC Use-Dilution Test method. We take many measures to reduce test-to-test variability, have successfully submitted data to EPA for project registration, and are eager to answer questions our customers may have with regard to this test.

For more information about the AOAC Use-Dilution Test, Contact the Lab Today!