ASTM E2784-Standard Test Method for Evaluation of the Effectiveness of Handwash Formulations Using the Paper Towel (Palmar) Method of Hand Contamination. ASTM E2784-10 (2015).
Test accredited by ENAC (National Accreditation Entity).
This test uses contamination from the hands of a group of adult subjects who will refrain from using any product containing antimicrobial agents for at least a week before the test. To do this, they will be provided with a personal grooming kit, without antimicrobial products, for exclusive use during the test. This test allows the option of using any of the following test organisms: Serratia marcescens and as alternative organisms: Escherichia coli, Shigella flexneri, or Staphylococcus aureus.
The test product is evaluated, previously performing a handwash to remove grease and dirt and subsequent contamination with the test organism that is incorporated into the surface of the wipe, spreading on it. In this way the subject contaminates the palm, fingers and fingertips that are in contact with the contaminated wipe. After this first contact of the hand with the organism a basal recovery is carried out, that is, a reference sample is taken after the first contamination to determine the number of viable organisms that survive in the hands. Subsequently, another cleaning is done to eliminate the residual sampling solution and the neutralizers, the subject's hands are contaminated again, pressing them on the contaminated wipes and the subject applies the reference product or the substance under evaluation, taking sample in both cases for evaluation. The results obtained in the plate counts (CFU/hand) are averaged and the log10 of the reductions are determined in each recovery/wash interval, a significant reduction that is evaluated by the Wilcoxon statistical method.
All the tests parameters will be equivalent in each case, being able to change the washing procedure for each product (in case it is different), both products being tested at the same time. The client must choose a contact time, a concentration and quantity of product in the trial or indications on how to add the product. The applicant for the test must state these requirements on the test form.