A. Dąbrowski

Reducing Kickback of Portable Combustion Chain Saws and Related Injury Risks: Laboratory Tests and Deductions

Abstract Portable chain saws are still very dangerous machines. Reduced prices of these machines mean they are widely available to people who like DIY (do it yourself) and professionals. Kickback of chain saws is extremely dangerous for the operator. This paper discusses the results of laboratory investigations of combustion chain saws. The tests were conducted on a standardized kickback test stand and covered the course of kickback, its energy, angle and duration. The results showed that during the contact of a saw chain with wood, the first to appear was the process of wood cutting, which absorbed 90–95% of the reduced energy of the cutting system. The greater the absorbed energy, the smaller the kickback angle. Wood cutting work is particularly influenced by proper chain tension, the use of chains with anti-kickback links, guide bars with sliding endings and a quickly activated chain brake.

An investigation and analysis of safety issues in Polish small construction plants

The construction industry is a booming sector of the Polish economy; however, it is stigmatised by a lower classification due to high occupational risks and an unsatisfactory state of occupational safety. Safety on construction sites is compromised by small construction firms which dominate the market and have high accident rates. This article presents the results of studies (using a checklist) conducted in small Polish construction companies in terms of selected aspects of safety, such as co-operation with the general contractor, occupational health and safety documents, occupational risk assessment, organization of work, protective gear and general work equipment. The mentioned studies and analyses provided the grounds to establish the main directions of preventive measures decreasing occupational risk in small construction companies, e.g., an increase in engagement of investors and general contractors, improvement of occupational health and safety (OSH) documents, an increase in efficiency of construction site managers, better stability of employment and removal of opposing objectives between economic strategy and work safety.

Kickback risk of portable chainsaws while cutting wood of different properties: laboratory tests and deductions

Portable chainsaws are associated with substantial risk and can cause serious injury to operators, especially during kickback. This paper presents new results from research and analyses conducted regarding the impact between the different properties of wood on this occurrence. In an open area, such differences may include: wood species, humidity, temperature and the facing angle of the wood fibres in relation to the kerf and shape of the wood surface that comes in contact with the tip of the guide bar. This paper investigates chainsaw kickback including the research results on kickback and wood-cutting energy, saw chain speed and the efficiency of the chainsaw engine. It also presents conclusions drawn from the tests that can be useful for chainsaw users, showing the dependencies between the different properties of wood and the risk of injury.

An application of the Pareto method in surveys to diagnose managers’ and workers’ perception of occupational safety and health on selected Polish construction sites

The construction industry is an important sector of the economy in Poland. According to the National Labour Inspectorate (PIP) data of 2014, the number of victims of fatal accidents in the construction sector amounted to 80 as compared with 187 injured in all other sectors of economy in Poland. This article presents the results of surveys on the impact of construction worker behaviour on the occupational safety and health outcomes. The surveys took into account the point of view of both construction site management (tactical level) and construction workers (operational level). For the analysis of results, the method of numerical taxonomy and Pareto charts was employed, which allowed the authors to identify the areas of occupational safety and health at both an operational and a tactical level, in which improvement actions needed to be proposed for workers employed in micro, small, medium and large construction enterprises.