ASTM E2276-10 (2019). Standard Test Method for Determining the Bacteria-Eliminating Effectiveness of Hygienic Handwash and Handrub Agents Using the Fingerpads of Adults.
Test accredited by ENAC (Spanish National Accreditation Entity).
Test with the Certificate of Good Laboratory Practices (GLPs).
This method aims to evaluate the eliminating efficiency of bacteria in hygienic handwash and handrubs, placing a test bacterial suspension on the tips of adult fingers to simulate the contamination of the hands with transient microflora. The dry inoculum located on the fingertips is treated with the test and control solutions. The test uses contamination of the hands of at least three adult subjects in duplicate for each combination of test substance to be analyzed. Subjects will refrain from using any product containing antimicrobial agents for at least one week before the test, providing them with a personal hygiene kit without antimicrobial products, of exclusive use during the test. Hands are washed and contaminated with any of the following test organisms; Serratia marcescens, Escherichia coli, Acinetobacter baumannii, Staphylococcus aureus, or Staphylococcus epidermidis. The exposure time of the test substance must be a time representative of the actual conditions of use, for at least 10 seconds and not more than 30 seconds, with a maximum of 10 complete inversions of the vial over the fingertip. In case of viscous formulations, the vial will be inverted and kept in contact with the contaminated areas for the desired contact time, no investments being made and in case the test method needs to simulate a post-treatment handwash, the fingertip will be exposed to 1 mL of hard water for 5-10 seconds before bacterial elution. The assay allows the incorporation of an entry control, control of viability of bacteria remaining after the inoculum has been allowed to dry, a control of bacteria eliminated after treatment with the test and reference substance and up to four replicates to evaluate the effectiveness in the reduction or elimination of bacteria under the test product. In this way, the results obtained are compared with a reference product and the results obtained from the test substance, taking into account the bacterial viability after drying, which will be used as a baseline to determine the degree of bacterial elimination after the treatment. The test may or may not use an interfering substance, consisting of a solution of one or more organic compounds and/or inorganic substances, added to the bacterial suspension to simulate the presence of body secretions, excretions or other foreign substances.
In order to consider effective the action of the handwashing disinfectant product, a significant reduction must be demonstrated in the individuals whose washing has been carried out with the test product compared to those whose washing has been carried out with a reference product, a reduction that is evaluated by the statistical method of Wilcoxon. The customer must choose a test concentration, a contact time between 10 and 30 seconds, indicate whether or not to add interfering substance in the test and whether the test method needs to simulate a post-treatment handwash. The applicant for the test must record these requirements on the test form.