The article analyzes factors that may have an impact on Occupational Safety in a construction company and the issues of work safety in construction were discussed. An attempt was made to analyze the management of work safety in construction companies in order to identify important factors and determine the significance of their participation in the occurrence of accidents at work. The research was carried out on the basis of data obtained from the register kept at the District Labor Inspectorate in Krakow. Cases which were discussed included accident protocols prepared pursuant to the law, as well as cases found in protocols of ad hoc inspections carried out on construction sites. There were quantitative and qualitative features in the analyzed data set. Logistic regression was used to analyze the data to build the model. Such action made it possible to model and determine the significance of the influence of individual variables characterizing the way of managing work safety in construction companies, in the case of an accident. The results obtained, and in particular the significance of factors shown in the model, even not directly related to the construction site, may be an indication for creating a functional strategy in the enterprise. The strategy assuming: smaller number of accidents or adverse events, shorter downtime will build a reputation of an institution that cares for the employee. This will allow the construction company to become more competitive and shall attract the best professionals available on the labor market. The end result is the identification of key factors that have a direct impact on work safety and the competitiveness of a construction company.

Crane selection is an important issue in assembly works planning. Tower and telescopic, stationary and mobile cranes used in construction have essentially different properties. Assembly planning begins in analyzing the possibilities of assembly with a given crane. This is called technical aspect of crane selection. Cranes that meet the technical criteria are then analyzed in terms of other criteria related to the effectiveness of their use on the construction site. The article presents the assessment of the selection criteria and the method of crane selection itself. Surveys conducted among construction managers and planners in Polish companies dealing with assembly works allowed to determine the significance of the selection criteria. For this purpose, an example using SAW (Simple Additive Weighting) and FSAW (Fuzzy Simple Additive Weighting) methods was presented. They also allowed to propose a technique for determining preferences in the use of selected construction cranes. The aim of the research was to increase the usability of computer applications supporting assembly planning by acquiring expert knowledge for the initial selection of organizational solutions.

An ancient forging device in Spain has been studied, namely the forge with a waterwheel and air-blowing tube or hydraulic trompe, found near the village of Santa Eulalia de Oscos (province of Asturias, Spain). Three procedures using ad hoc methods were applied: 3D modelling, finite element analysis (FEA), and computational-fluid dynamics (CFD). The CFD results indicated the proper functioning of the trompe, which is a peculiar device based on the Venturi effect to take in air. The maximum air volume flow rate supplied to the forge by the trompe was shown to be 0.091 m3/s, and certain parameters of relevance in the trompe design presented optimal values, i.e. offering maximum air-flow supply. Furthermore, the distribution of stress over the motion-transmission system revealed that the stress was concentrated most intensely in the cogs of the transmission shaft (a kind of camshaft), registering values of up to 7.50 MPa, although this value remained below half of the maximum admissible work stress. Therefore, it was confirmed that the oak wood from which the motion system and the trompe were made functioned properly, as these systems never exceeded the maximum admissible working stress, demonstrating the effectiveness of the materials used in that period.