Integrating environmental assessment of failure modes in maintenance planning of production systems

Apart from preventing and controlling economical, technical and safety impacts of failures, so to reduce at best production losses, maintenance target is to systematically check and improve the allocation and usage of resources in order to assure quality of products and processes. At the same time, consumption of resources and their relative environmental impacts are becoming a central issue in the new international regulations and standards for sustainable manufacturing. On these considerations, the paper proposes an innovative methodology that, starting from the principles of FMECA (Failure Mode, Effects and Criticality Analysis), extends its own concepts with the introduction of a specific index to measure environmental effects of failures. Starting from the traditional definition of the RPN (Risk Priority Number) of a failure mode, the approach defines a new indicator (Environmental Indicator) to extend the results of FMECA and take in consideration the most critical issues of environmental protection: consumption of materials, emissions and wastes, lifespan of systems. Using this tool, maintenance scheduling can be defined considering also an environmental perspective. The methodology is tested on the maintenance program of a manufacturing line in a pharmaceutical production system and results are compared to the one obtained using a traditional FMECA approach.