However while the hand dryer exists in the singular here, there is one of them, it's described in the plural. It's quite possible that someone was asked to "make some signs for the hand dryers" with them being in different places - at least the ladies and the gents - and maybe because to some it might not look much like a dryer at first glance.
Another alternative is that the radiator could be considered a dryer convecting heat upwards while the hand dryer projects heat downwards. Maybe that's why there's such an explicit encouragement to "Value the Experience".
