QR codes belong to the group of two-dimensional codes and are able to save a lot of information on a small area while being simple to use. Therefore they are ideal for the application in maintenance procedures. The idea of this thesis was to deal with the issues concerning the usage of QR codes in maintenance procedures. Also the influence of the size of soling will be examined, in the means of the very coverage of codes and consequently their readability. Next step will be to determine the influence of the stain position on the code readability, specifically speaking will the code be readable no matter what the position of the stain is, and in the end to determine how to influence the preservation of it’s readability. Also a small research will be conducted trying to determine which dimensions of the QR codes would be adequate for the usage in mentioned application. The research will be defined and explained in the experimental part of the thesis while the theoretical part will be concerned with concepts of maintenance, QR codes and their implementation. The goal of this thesis is to determine the effects of stains on the code, wheter it is their size or position on the surface of the code.