"if hands were scrubbed, rinsed, and dried properly." ... which never happens. Seems like the same faulty logic used to justify blow-driers over paper towels.

"if hands were scrubbed, rinsed, and dried properly." ... which never happens. Seems like the same faulty logic used to justify blow-driers over paper towels. It doesn't look like the study that would actually answer this question (randomly assigning bathrooms heated and unheated water, doing hand swabs on leaving patrons) has actually been done, but if I were in a position to gamble on the outcome, I'd bet the cold water bathroom gets substantially less effective cleaning for human-factors reasons.