PERSPECTIVE OF THE SYSTEMATIC AND EXTENDED USE OF TEMPORAL AND SPATIAL-ASPECTS IN LCA OF LONG-LIVED PRODUCTS

Recent scientific discussions indicate a special need to consider temp oral aspects in LCA of long-lived products. Elements thereof are alrea dy used for several impact categories such as those being related to c limate changes. However, the elements are not used in a systematic and identical way for all categories. They are a basis for deriving chara cterisation factors and are based on the implicit assumption of a sing le discrete emission occurring ('')now''. They do not allow for calcul ating time-dependent loadings arising from multiple, discrete or conti nuous emissions over a given (future) time horizon, though these prede fined time horizons are needed to model both, fate and (abiotic/biotic ) effects once the emission has taken place. A systematic way to intro duce temporal aspects is presented. As a consequence, the need to modi fy characterisation factors already considering temporal aspects such as residence times is discussed. Alternatives outside LCIA are also pr esented. (C) 1998 Elsevier Science Ltd. All rights reserved.