It has been presented selected results of investigations oriented on identification, analysis and assessment of fume and chemical hazard which occur during application of innovative methods of joining various construction materials as well as on disclosure of the possibility of optimization of these methods in respect of the improvement in work conditions and the increase in work safety during fabrication of welded structures in different industrial branches. The results of the project “Assessment of fume and chemical hazard in work environment during joining various construction materials by innovative methods as the action supporting the formation of safe work conditions” executed under the Long-term National Programme “Improvement in safety and work conditions” have been given as well.