Microsystems technology competitionVDE gives the go-ahead for 'Cosima 2016'

... measures the effects of the destruction of germs in PET bottles through exposure to UV radiation. In the 'Sodis' (Solar Water Disinfection) method, water is placed in a transparent PET bottle and left in the sun for six hours. The UV light contained in the solar spectrum kills germs and pathogens. However, clouds or a scratched bottle prolong the required cleaning time, so that people consume germ-contaminated water after six hours and fall ill. The students therefore developed a reusable, wear part-free indicator that monitors the cleaning process in the bottle and interacts with the user in a simple way via pictograms. This prevents misuse and the resulting illnesses and mistrust of the cleaning method. It also makes the method more accessible for children and illiterate people.