I don't know which GFSI scheme you are trying to meet but SQF states that you need potable water at an appropriate temperature. I look at it as the water temperature should be inviting to encourage the employees to wash their hands. You don't want the water to take too long to warm up from being cold because people are impatient and may choose not to wash their hands or will not do a very good job. I have had to wash my hands with cold water and it is very unpleasant, especially if you are already cold. Also, too hot can be a problem as well.
We did have one auditor that did count when he tested our hand washing stations and he said he looks for the water to warm up within 30 seconds. I don't know where he got his number from but it was the standard he went by. My personal point that I made to our management team on this subject is that the water should be warmed within 20-30 seconds as that is about the minimum amount of time one should be lathering his/her hands with soap so by the time one is ready to rinse his/her hands the water should be a comfortable temperature. If you have automatic faucets it can make it more challenging if the water turns off as soon as you remove your hands from under the spout as the water does not consistently run allowing the water to run through the pipes so you may need an instant heater for the hand wash station.
