Life cycle risk assessment (LCRA): description of this methodological proposal and a case of study
Résumé
The life cycle of a product is generally characterized by the main following stages: Raw materials acquisition, Manufacturing, processing and formulation, Distribution and transportation, Use, re-use, maintenance, Recycle and Waste management. Considering the life cycle thinking in a risk analysis approach requires the adjustment of the classic risk analysis methodology. In order to build up this new methodology called Life Cycle Risk Assessment (LCRA), we relied on the Life Cycle Assessment (LCA) methodology, which allows the assessment of the potential environmental impacts throughout the life cycle of a system. Once these adjustments made, this LCRA new methodology is explained and applied to two energy pathways for transportation sector: hydrogen (produced from the biomass) and gasoline pathways. The life cycle thinking is not taken into account in the traditional method of risk analysis. To integrate this fundamental concept to the risk analysis methodology following the model of the LCA (Life Cycle Assessment) methodology (ISO 14 040, 14044 and the ILCD Handbook), we made some adjustments to the risk analysis methodology. Each of the LCA's four steps has its counterpart in terms of LCRA (Life Cycle Risk Assessment). The variations between these two methodologies reside on two key steps of the LCA: the inventory (step 2) and the assessment (step 3). The inventory collects data whose nature is different between the two tools. For LCA, collected data are matter and energy flows; these data are qualitative and quantitative ones. For LCRA, the data collected are only qualitative since it is an inventory of dangerous situations. The assessment step consists of three sub-steps: classification, characterization and valuation, and allows a conversion of inventory data into results of impact / risk levels. For LCA, the conversion of inventory data is performed by a calculation using characterization factor. For LCRA, this conversion is done qualitatively by rating and prioritizing risks. However, the goal of sub-step classification is the same in both tools because it links the inventory data and the impacts/risk to be assessed. Just like the flow identified by a LCA that can contribute to different categories of impacts, dangerous situations can cause different types of accidents. Therefore, limitations and hypotheses should be established to make the LCRA methodology usable and relevant in view of the objectives and the applicability of the expected results. Additional file Life Cycle Risk Assessment (LCRA): description of this methodological proposal and a case of study.