Page 81 - Materials Chemistry, Second Edition

3.1 Basics 65

James Fava and co-workers, 10) and Ian Boustead. 11) In a more recent text, Fleischer
and Hake 12) discuss LCIs in detail. The international standard dealing with LCI
13)
has been, from 1998 to 2006, ISO 14041 ; since October 2006 LCI has become
part of ISO 14044. 14) Regional guidelines and standards have been elaborated
in Scandinavia, in the USA, France, 15) and Canada. 16) Scandinavian guidelines
are documented in the ‘Nordic Guidelines on Life Cycle Assessment’ 17) and
have been further elaborated in the Danish EDIP programme (Environmen-
tal Design of Industrial Products). 18) US-EPA has commissioned guidelines for
the conduct of LCAs by the Battelle Memorial Institute and by Franklin Asso-
19)
ciates. A newer publication is available from the European Joint Research Centre
(JRC). 20)
In German-speaking countries, the Swiss publications of BUWAL 21) have for
long almost been standard, in particular for Inventory Analysis and its relevant
data. The original, German version of the monograph and textbook ‘ ¨ Okobilanz
(LCA)’ 22) contains some official variants of LCA, which are typical for Germany.

3.1.3
The Unit Process as the Smallest Cell of LCI

3.1.3.1 Integration into the System Flow Chart
A system flow chart as a diagram of the examined product system consists of small
boxes where the processes involved are specified and their mutual dependencies
are indicated by one- or two-sided arrows (Figure 3.1).
As long as a linear approximation is adequate, branching will occur at some boxes
(see Section 3.1.4) but there will be no formation of networks. The small boxes
(1,2,3,4 … n, m), which can, for instance, designate production or processing
steps of a product, are called unit processes.
According to ISO 14040, these are the smallest elements considered in LCI for
which input and output data are quantified (Figure 3.2). With large data resolution
the unit process can correspond to a printing process, a transportation procedure,
a metal deformation, a filling, a cleansing, a single chemical reaction, and so on; if
less data are available (or for small data resolution), these can refer to a plant or to
a side chain, for example, ‘production of electricity’ (see Section 3.4.3).

10) SETAC (1991).
11) Boustead and Hancock (1979) and Boustead (1992, 1995b).
12) Fleischer and Hake (2002).
13) International Standard Organization (ISO) (1998a).
14) International Standard Organization (ISO) (1998a) and ISO (2006b).
15) Association Franc¸aise de Normalisation (AFNOR) (1994).
16) Canadian Standards Association (CSA), 1992.
17) Lindfors et al. (1994a,b, 1995).
18) Wenzel, Hauschild and Alting (1997) and Hauschild and Wenzel (1998).
19) EPA, 1993; EPA, 2006; see also EPA’s LCA Web site: www.lcacenter.org/InLCA.
20) http://lct.jrc.ec.europa.eu/pdf-directory/ILCD-Handbook-General-guide-for-LCA-DETAIL-online-
12March2010.pdf, pp. 70–87.
21) BUWAL (1991) and BUWAL (1996, 1998).
22) Kl¨ opffer and Grahl (2009).