A third of New Zealand's schools are using hand driers that are potentially leaving children's hands dirtier than when they left the toilet cubicle.
The findings come from a study in which 400 New Zealand parents and 100 schools were asked about washroom hygiene.
SCA Hygiene Australasia commissioned the study in a bid to learn more about washroom behaviour, fears about the forthcoming flu season and the best way to reduce bacteria on hands during the drying process.
SCA spokesman Mark Stevens said not all hand drying methods were created equal - but not everyone was aware of that fact.
"Most people know that washing your hands with soap and water is important but it is the method that you then use to dry them that determines how clean your hands are.
"The key is getting your hands dry because germs thrive in a moist environment."
Mr Stevens quoted research from the University of Westminster which found warm air driers increase the bacteria on hands by up to 254% - a fact which came as a big surprise to nearly three-quarters of the parents surveyed.
The survey also found 90% of parents wanted their children's school to improve hygiene levels in washrooms.
Only half of schools were worried about the forthcoming flu season.
Nearly two-thirds of New Zealand's schools said they already had paper towels, but they were more common in primary than secondary schools and in schools with fewer than 100 pupils.
It also found that 2% of the schools surveyed had no hand-drying devices.
Overall, the study concluded that paper towels would "completely dominate the market" if hygiene alone was the sole factor.