surgical scrub with brushASTM E1115 Evaluation of Surgical Hand Scrub Formulations

The ASTM E1115 test uses what are called glove juice sampling techniques to measure the reduction of immediate and persistent bacteria on hands after single or multiple treatments using Surgical Hand Scrub products. For this testing a supervised surgical scrub is completed before one hand for each subject is immediately tested. 6 hours after the surgical scrub treatment the second hand is tested for surviving microorganisms. If the cumulative antibacterial effect of the surgical scrub is to be evaluated, testing may be continued over the course of a 5-day period to profile the cumulative effect of using the product.

ASTM E1115: Procedure At a Glance

In this study, healthy subject individuals with high levels of bacterial flora are chosen from a group of study participants who have not used antimicrobial products for the week preceding the test. An initial 7 day “Baseline Period”, which includes three non-antimicrobial washing, sampling, and enumeration steps, is used to obtain the baseline hand bacterial populations. Subjects who had >1 x 105 CFU/hand at each sampling time are selected as test subjects.

A balanced randomized plan is then used to test a group of at least six of the selected study subjects. These subjects must have completed the “Baseline Period” 24-96 hours before they perform the prescribed surgical scrub treatment with the test formulation. Hands are then sampled for surviving microorganisms zerothree, and six hours after the treatment wherein the three hour sampling interval is optional and where samples are recovered using the glove juice sampling technique. The immediate activity measurement are the results obtained immediately following a single scrub (zero hour sampling interval). Persistent activity, or a continuing antimicrobial effect, is measured using the data from the later samplings. In order to obtain cumulative effect measurements, the hands may be sampled after completing 11 additional scrubs with the antimicrobial product over a 5 day period.

The average number of survivng microorganisms recovered for each hand sampled at each sampling time are calculated, and the changes from the baseline counts are determined. The mean log10 reductions and the 95% confidence intervals for the test formulations after 1 or 5 days use are calculated. For persistent and cumulative activity, analysis of variance techniques are used to evaluate differences between sampling intervals. The validity of the test method within a study is determined using an internal reference formulation and a negative control.

ASTM E1115: Vivo Clinical Testing’s Expertise

Vivo Clinical Testing was founded in 2017 by Dr. Benjamin Tanner, a respected microbiologist and owner of Microchem Laboratory and is staffed by many experienced Microchem Laboratory employees.  Vivo is committed to providing the same high testing standards that have been demonstrated by Microchem Laboratory since 1988.

Vivo Clinical Testing Is:

A contract testing laboratory designed to support the hand hygiene and infection control industry. Testing is carried out in compliance with current FDA, Good Laboratory Practice (GLP), and Good Clinical Practice (GCP) regulations by skilled, experienced microbiologists and chemists, to quickly meet your project testing goals.

Vivo Clinical Testing Is:

An FDA GLP and GCP-compliant testing organization staffed by skilled, experienced microbiologists and subject recruiters.  Vivo can help speed your project to completion.

Quick Contact