Our planet is threatened by climate change, caused by the increase in greenhouse gases (GHG). The involvement of human activity has been recognised. We cannot measure GHG emissions everywhere, because they come from multiple sources. But that is no reason to give up on the idea. Engineers have invented indirect evaluation methods. Chemical analysis of any fuel reveals how much GHGs are released into the atmosphere by combustion. The same applies to all materials used in industrial production processes.
Environmental life cycle analysis (ELCA)
If we record all these indicators on a database, and we know the quantity of each material to be burned during manufacture, we can deduce the quantity of GHG generated. We can do the same for the other substances entering and exiting the system. This has been done, from planting a tomato shoot in the field and aluminium extraction in the mine, to supplying a tin of tomatoes to the supermarket. The method enabling this calculation to be performed is known as an LCA (Life Cycle Analysis). It relates to all or some of the manufacturing, usage and recycling stages of a product (stages describing the product “life cycle”, hence the name of the method). It enables us to quantify the potential consequences of the existence of the life cycle, in terms of ecological damage. It is useful for comparing various solutions for achieving the same service rendered, in terms of their ecological impacts.
Social Life Cycle Analysis (SLCA)
But the ecological effects are not the only ones of interest to public or private decision-makers. Hence the idea of developing a method comparable to the ELCA, but for estimating the social effects. The term “social LCA” was created in 1995, without any specific consensual content. The aim of the social LCA is to quantify the social consequences caused by the workings of a particular life cycle, and by the changes involved in this cycle.
From 2006, authors started suggesting causal chains for calculating the social consequences of changes in the life cycle. In parallel, others focused on estimating social performances of the constituent companies of the life cycle. Together all these evolving works represent the field of analysis of the social life cycle.