摘要：Drinking tap water has recently become popular. It is a way to fight with the tons of garbage (disposable, plastic bottles). However, many people are afraid of water quality. The research was performed in December 2015 in Krakow, during one week. 56 samples were collected. The samples were taken in different times of the day and in the two types of building (old one with installation from the 80s and new one with installation built in past few years). Samples were taken by two qualified operators. The first sample was collected at the morning at 6 a.m., before anyone uses the tap. The second one after the tap was flushed and then the third one after 30 minutes stagnation. At the evening was taken one sample (after using the tap all day).The aim of the research was to check the quality of drinking water in the end-user. The results show that quality of tap water in Krakow is good, also in the end-user, but the concentration of chemical elements are changing during the flushing and using of the tap.
