DId you know you can work out maths behind the 20 second hand wash we do to fight coronavirus? On average we wash our hands four times a day in school- after break, before lunch and when you go to the toilet. The rest of the time we sanitise. I wondered how much water the hand washing in school would use? I measured how much water is used in a 20 second handwash, about 1 litre. That is 4 litres a day, 5 days a week that is 4x5=20 litres. There are 58 students in our school so that is 20x58; 10 x58 is 580 so 20x58 is double that, 1160 litres. So our school uses 1160 litres a week washing hands.
