Cliched or not, those old stories about people not washing their hands after using the lavatory really aren’t funny.
Today’s invention represents a low cost way for an organisation (including eg a hospital) to monitor handwashing among its staff…and thus consider the urgency of conducting an in-house hygiene campaign.
For each washroom, take a credit card calculator and place it in the door frame with only the “+” button left exposed (the others could be prised out of the keboard). Every time the door springs closed, this device will add 1 to the ongoing total.
Repeat the exercise with the push plate on the hand dryer units (this will require removing the outer cover and placing a calculator behind each plate).
After a few weeks, the ratio between total number of door openings and the number of hand drying occurrences can be calculated. If the figure differs significantly from 1.0, then maybe eating those peanuts at the christmas party is a bad idea.