With regard to cut-off criteria, which are used to decide
whether processes shall be included in the product system
and data gathered, a level of 2 % based on mass was
applied. In other words, the process is neglected if it
reaches less than 2 % of the total known mass. All
processes with available data were taken into account,
even if their contribution is less than 2 %. Therefore,
the cut-off rule is used to avoid gathering unknown data,
but not to neglect the known