Canker sore: A canker sore, also known as an aphthous ulcer, is a single pale or yellow ulcer with a red outer ring or a cluster of such ulcers in the mouth, usually on the cheeks, tongue, or inside the lip.
The Board will allow a maximum temperature of 120 degrees Fahrenheit. Hand sinks in commercial kitchens are only used by employees. These employees are typically washing and rinsing pots and pans in pot sinks which could have 140 degree water. Those pot sinks, in some kitchens are located right next to the hand sinks.
It's worth mentioning that modern soaps are still effective at colder temperatures; so, if you don't have access to heated water, it's still better to wash with cold water and soap than with no soap at all [source: Hand Washing for Life]. With the proper water temperature in place, you're ready to move on to methods for washing your hands.