Single-use towels shows lower level of airborne microbe dispersal than other hand drying methods, study finds

Single-use towels present the lowest risk of cross-contamination

New research by the University of Westminster, in London, UK, commissioned by the European Tissue Symposium (ETS), concludes that drying hands with single-use towels shows a lower level of airborne microbe dispersal and contamination.

The study, by microbiologist Keith Redway, who presented top line findings at last year’s HIS Conference in Lyon, France, looked at the potential for microbial contamination from hand-drying and the potential risks for airborne microbe dispersal.

Four hand drying methods and three test models were used to determine differences between the drying methods and their capacity to disperse microbes on the hands of users to other occupants of public washrooms and into the washroom environment.

Paper towels, a textile roller towel, a warm air dryer and a jet air dryer were compared using three test models: acid indicator with lemon juice, yeast, and bacterial transmission from hands when washed without soap.

The study was published in the March 2015 edition of the Journal of Hospital Infection.

The results revealed that a jet air dryer dispersed liquid from users’ hands further and over a greater range – up to 1.5m – than other hand drying methods. The jet air dryer also led to the greatest dispersal of microbes into the air at both near and far distances for each of the tested models.

Hand drying using single-use towels offers an unsurpassed level of hygiene when drying hands

Levels recorded at the drying device revealed an average of 59.5 colonies of yeast for the jet air dryer, compared with an average of 2.2 colonies of yeast for paper towels. At a distance of 0.2m jet air dryers resulted in 67 colonies compared with only 6.5 for paper towels. At a distance of 1.5m the jet air dryer recorded 11.5 colonies of yeast compared with none for paper towels.

The study also looked at the body height at which microbes were dispersed. It found that the greatest dispersal was at 0.6m–0.9m from the floor. This equates to the face height of a child who might be standing near a dryer when a parent is drying their hands. The child might therefore be contaminated with the microbes remaining on the parent’s hands after washing.

Roberto Berardi, Chairman of the ETS, said: 'This latest research by the University of Westminster builds on previous studies such as last year’s research by the University of Leeds, and adds to the existing body of evidence demonstrating that hand drying using single-use towels offers an unsurpassed level of hygiene when drying hands after visiting the washroom and is associated with lower numbers of microbes both on the hands and in the washroom environment than with warm air or jet air dryers.'