When it comes to formulation of ABHR it is important to get the facts

Across the market today there are various formulations of alcohol-based hand rubs (ABHR) with different alcohol concentrations and formats (gel, foam, rinse) and dispensing methods which can make the selection process difficult for your environment.

The three confusing elements when choosing an ABHR for your area are:

• Do all ABHR achieve the same efficacy?
• Does a higher alcohol concentration deliver greater efficacy?
• Is a gel better than a foam ABHR?

How are ABHR evaluated for antimicrobial efficacy?

There are two general types of testing performed to demonstrate that formulations are efficacious: the in vitro which are performed in the lab and the in vivo, typically performed on the hands of human subjects and are intended to measure the activity of products during actual use conditions. In vivo tests predict the reduction of organisms achieved by the use of hand sanitisers after handling contaminated objects.

In vivo tests are done using standard global protocols such as the European Norm EN 1500 and the American Society for Testing and Materials ASTM E1174 (health care personnel hand wash [HCPHW]). Both are recommended by the World Health Organization (WHO) and other Health organisations such as the Centers for Disease Control and Prevention (CDC).

Formulation of ABHR is critically important and matters

GOJO have conducted a study published in the American Journal for Infection Control (AJIC) (Edmonds et al., 2012) to understand better the relative influence of alcohol concentration, product format, and total product formulation on ABHR efficacy. Several ABHR formulations available in the market containing alcohol concentration ranging from 60–90% were compared using the in vivo ASTM1174 test.

Results showed that product formulation as a whole, not the alcohol concentration, is a more important factor for the antimicrobial efficacy. Two novel ABHRs based on 70% ethanol have (PURELL been XXX) performed better than ABHR with higher alcohol concentration. Varying the alcohol had very little influence on product efficacy. Formulation Matters and is more important than alcohol concentration alone.

In conclusion, these studies collectively demonstrate that PURELL Gel and Foam have the same efficacy that meets global efficacy standards when used at volumes (1.1 ml) that more accurately reflect use in clinical settings. Finally, product format and alcohol content (within the range of 60%–95% [vol/vol]) are not the key drivers of product efficacy.