Estimation of work efficiency is one of the important tasks in company management and analysis of workers’ activities. The environment for determining the efficiency of workers is the use of one or more IS of any kind, within the framework of which the worker’s duties are accomplished. This process can be performed both from home (isolated from the work environment and co-workers) and in the office on-site. Another aspect is related to the fact that a worker can work both with only one IS, or with multiple specialised systems in parallel, which requires the simultaneous integration of several data sources and the parallel reading and analysis of information relevant to worker activities. The task of work efficiency estimation is especially complicated if the company’s activity domain is narrowly specific. In this case, solving such a task of working hour accounting and efficiency estimation is not a trivial accumulation of statistical data, but requires a dedicated method. The work of an engineering system designer is one of the examples of such specific activities. Therefore, exactly this domain was chosen as an application case of the method and metrics proposed in the paper.