In particular:

• The ‘upstream’ phase includes all the processes upstream which occur at the beginning of the value chain (e.g. extraction of raw materials, production of purchased goods, transport of same to the production sites) and before production;

• The ‘core’ phase concerns actual production of the product and includes the activities which take place within the confines of the system analysed;

• The ‘downstream’ phase includes all processes downstream of the system analysed which occur at the moment in which the good leaves through the company gate (e.g. distribution, product use and end life).

At times these phases can be grouped differently as in the case of the classification adopted by the GHG Protocol.

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