How hot does water need to be when you wash your hands?
It has long been supposed that hot water works to get bacteria off your hands better than cold water. But the hot water needed to kill bacteria is way too hot to be comfortable to use when washing your hands.
Luckily, studies have proven that hot water is not necessary to use while hand washing. In fact, in a 2005 study documented in the Journal of Occupational and Environmental Medicine, participants were instructed to wash their hands in water ranging from 40 degrees all the way up to 120 degrees. What the study found is that the temperature of the water doesn’t really matter when it comes to getting your hands truly clean.
