ASTM E2755-10

Hand hygiene is considered one of the most important measures for preventing the spread of infectious microorganisms. Hand sanitizers reduce the microbial load on the hands without the use of soap and water, and are thus an important tool in the practice of good hand hygiene. Hand sanitizers are recommended for use on hands that are not visibly soiled. They are formulated to be applied full strength to dry hands, “rubbed in” until dry, and are not rinsed off.

This test method is specifically designed to evaluate the bacteria-eliminating activity of hand sanitizers from experimentally-contaminated hands. It is intended to be an alternative to Test Method E1174, which was designed primarily to evaluate antimicrobial handwashing agents that are lathered with the aid of water and then rinsed off. When using Test Method E1174 to evaluate hand sanitizers, inadequate drying of the hands after contamination dilutes the test product and can compromise activity, leading to an underestimation of effectiveness. By applying a higher titer test bacteria suspension in a smaller volume, soil load on the hands is minimized and hands are completely dry prior to application of the test material. These modifications result in a better approximation of the in-use conditions for hand sanitizers and thus provide a more reliable indication of their performance in the field.

This test method can be used to test any form of hand sanitizer, including gels, rubs, sprays, foams, and wipes according to label directions at typical “in-use” doses.

Susceptibility to biocides can vary among different species of bacteria and major differences have been noted between gram-negative and gram-positive organisms. This test method provides the option to use either a gram-negative bacterium (Serratia marcescens) or a gram-positive bacterium (Staphylococcus aureus) as the test organism. S. marcescens is used as a test organism in both Test Method E1174 and Test Method E2276. S. aureus is a highly relevant pathogen in healthcare, institutional, and community settings. Moreover, hands are an important vehicle in the transfer of S. aureus between people and the environment, and in the transfer between individuals.

This test method may be used as an alternative to Test Method E2276, which limits the test bacteria to the fingerpads and does not incorporate actual use conditions such as friction during hand decontamination.

The investigator should be aware of potential health risks associated with the use of these organisms and precautions similar to those referenced in Section 8 should be taken.

1.1 This test method is designed to determine the activity of hand sanitizers (also known as hand rubs, hygienic hand rubs, or hand antiseptics) against transient bacterial flora on the hands.

1.2 Performance of this procedure requires the knowledge of regulations pertaining to the protection of human subjects (see 21 CFR Parts 50 and 56).

1.3 This test method should be performed by persons with training in microbiology, in facilities designed and equipped for work with potentially infectious agents at biosafety level 2.

1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For more specific precautionary statements, see 8.2.