ASTM E2755–22. Standard Test Method for Determining the Bacteria-Eliminating Effectiveness of Healthcare Personnel Handrub Formulations Using Hands of Adults.

Test Accredited by ENAC (Spanish National Accreditation Entity).

This test uses contamination of the hands of at least eight adult subjects, for each combination of test substance to be analyzed. Said subjects will refrain from using any product containing antimicrobial agents for at least one week before the test, providing them with a personal grooming kit, without antimicrobial products, for exclusive use during the test. This test method provides the option of using any of the following test organisms: a gram-negative bacterium (Serratia marcescens) or a gram-positive bacterium (Staphylococcus aureus).

The test product is evaluated after a single application and after ten consecutive contaminations/applications in a single day, previously performing a handwash to remove grease and dirtiness (the standard strongly recommends that it be chosen as test bacterium Staphylococcus aureus ATCC 6538, when multiple cycles of contamination/application must be carried out). When evaluating the effectiveness after multiple applications simulates the repeated use of handrubs in clinical environments and determines whether the progressive accumulation of the non-volatile ingredients of the test material inhibit the action of the antimicrobial. The assay allows to include a reference control (60% isopropanol), which is evaluated for each subject before evaluating the test substance. The results obtained in the reference control help to control the variability between subjects, the inter-experimental variability and the inter-laboratory variability allowing to improve the statistical comparison of test materials evaluated in the same experiment. This test method can be used to test any form of handrub, including gels, rinses, sprays, foams and wipes using them according to the manufacturer/developer's specifications. The effectiveness of this substance, is measured by comparing the amount of bacteria recovered after the application of the test material with respect to the amount of bacteria recovered in the contaminated hands exposed to the reference material, the significant reduction is evaluated by the statistical method of Wilcoxon.

The customer must choose a contact time, a test concentration or manufacturer's instructions on how to add the product and the number of applications of the test substance that is to be incorporated in the test. The applicant for the test must record these requirements on the test form.