The key task of each library is to ensure its high performance. Under the conditions of limited economic resources, the rational use, first of all, of labor resources, is of particular importance. The study of the working time of library specialists allows the solvation of a set of issues related to the organization and rationing of their work. However, this type of research is conducted in libraries rather rarely. Problems of studying the working hours of specialists and employees remain without due attention. The existing methods have been developed and are intended primarily for industrial production and the study of workers’ labor. Libraries have to adapt them basing on their goals, tasks, and capabilities. The purpose of the article is to present the results of the development and testing of an original methodology to study the expenditures of working time of specialists in order to normalize labor in the Far Eastern state research library (DVGNB). The author compares the methods of data obtaining, evaluates the possibility of using different types of observation in library, and justifies the choice of the photo-timing method. The main attention is paid to the technology of observation. The main points of the preparatory stage are described in detail and that of processing the obtained data. As a result, the methodology to study the expenditures of working time and labor processes is tested, and it can be used in library practice to determine the structure of production activities and time for their implementation, to rationalize techniques and methods of work, to identify reasons for non-compliance of targets, unsustainable expenditures and loss of working time, to determine quantitative characteristics of personnel potential, etc.