Visit to the water testing laboratory

High School Markantun de Dominis Rab has been cooperating for many years with Vrelo d.o.o., a utility company for supplying the population and economy of the island of Rab with water. A visit to the laboratory for water testing is organized, where students are first introduced to the history of this Rab water source, Mlinica, as well as other water sources on Rab and the organization of the distribution of drinking water on the island. Students are introduced to the devices and laboratory utensils needed for analysis in the water quality testing laboratory. They learn how to test water for different elements such as chlorine, different forms of nitrogen, how to measure the temperature, hardness and turbidity of water. They learn that water needs to be desalinated in order to be drinkable, what substances are allowed to be present in drinking water and in what quantity. In a bio-chemical laboratory, bacteria that should not be contained in water are observed under a microscope on water samples. Laboratories demonstrate to them how to make these samples and how to grow fungi from water samples.