With the football season over for another campaign, the arrival of milder weather brings with it the arrival of the car-washing season and, thanks to Citroën, the formula for the perfect way to clean your motor.
Citroën, the Official Car Supplier of Arsenal, together with an applied mathematician, devised that E = 1/t + 1W, where E is efficiency, t is the time taken for the car wash and W is the amount of water used.
The car manufacturer decided to test out the calculation by asking Per Mertesacker, Aaron Ramsey and Olivier Giroud to create the 'premier' car wash for Club captain Thomas Vermaelen. The results can be seen above.
In researching the formula, Citroën's various vehicles were washed by people of differing heights in a selection of weather conditions, ranging from 4 to 20C. The average amount of water used and the time taken was then calculated to suit the outside temperature.
For example a 6ft 4in car washer, such as Per Mertesacker, should take 31 minutes to clean a supermini-sized car in a low, ambient temperature of four degrees centigrade with 24 litres of water.
The research also found that, if the vehicle hasn't been cleaned for up to three months, or has visible road grime on more than 40 per cent of its surface, an extra 2.5 litres of water and an additional five minutes of elbow grease will be needed.
Citroën has devised five top tips to help ensure the car wash remains efficient, yet effective, by reducing unnecessary water wastage with either a bucket and sponge or a hose:
1. If possible, wash your car after a rain shower to avoid using additional water to rinse the car first
2. Find a shady spot to wash your car to avoid drying marks and repeat cleaning
3. Always wash the body of the vehicle from the top down
4. Wring your sponge or chamois out over the bucket
5. Use a sponge to wash down with one hand and, a chamois in the other to dry off immediately
Arsenal captain, Thomas Vermaelen, said: "We had good fun filming the video for Citroën. It was great to see the lads hard at work even after training had finished, getting the DS3 Cabrio spotless. I was pretty impressed by their cleaning skills, and control of the sponge balls!"
Professor Kenneth Dickens said: "This is the time of year when we want to spend more time outdoors, making the most of the sunshine, and what better way to do that than with a good old-fashioned car clean. The formula provides the perfect ingredients for a car wash taking into account all the variants - of course the formula doesn't account for the water wastage from family water fights!"