Virtual environments in machinery safety analysis

Safety is a feature that someone or some ones have planned for a product. To ensure that safety issues have been properly considered in the design phase of a product or production system different methods and procedures and tools have been developed. Safety analyses already in design phase have been basics for ensuring product or production system safety features. To engage all possible knowledge in the safety design participatory approach and different tools have been developed and implemented. The rapid development of computers and software has made it possible to investigate systems in virtual environments (VEs), which are potential tools for safety analyses in design phases. The use of virtual environments in safety analysis for production evaluation purposes have remained minimal, reasons being lack of methods and knowledge of their applicability in safety analysis. The objective of this work was to evaluate the impacts of VEs on safety analysis. A new method (SAVE) of applying VEs for safety analysis was developed and tested in the work settings. The method involves a procedure, based on Participatory Approach (PA), Task Analysis (TA), Work Safety Analysis (WSA), standard EN 1050 and three-dimensional (3-D) modelling of the objects being analysed. The materials of this thesis comprised machinery systems of five plants in a steel factory, implementing ongoing modernisation projects. The plants were hot steel storage plant, steel converter plant, secondary metallurgy station, continuous casting plant and strip production plant. The machinery systems were cranes, mixers, desulphurisation station, remote-handled cars, steel converters, ladle turrets, continuous casting machines, coilbox machine and coil conveyer. The results indicate that the SAVE method was applicable for safety analysis in machinery layout design phase. Safety analysis will clearly benefit from the use of VEs. According to the results 58% of all identified hazards in a steel factory could be identified with VEs. Simulation with a virtual environment was assisting the identification of hazards in 25% and digital human models in 10% of all identified hazards. A common understanding of designs, possibilities of evaluating and developing the system by the workers and of providing training for operators and maintenance persons were the major contribution when using VEs in safety analysis and applying participatory approach. VEs with an analysis group improved the identification of critical safety situations during the analysis. Once equipment and software for VEs have become more versatile and less expensive the usage of VEs in plant design and development work will increase. This, however, calls for further investigation of more effective implementation procedures and cost management. The use of VEs in plant design will enhance the development and analysis of different design variations from several points of view, including safety.