Page 61 - Materials Chemistry, Second Edition

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Life Cycle Inventory Modeling in Practice

Beverly Sauer
Franklin Associates, A Division of ERG, KS, USA

Abstract
This chapter focuses on the first two phases of LCA, goal and scope definition and
the life cycle inventory (LCI) analysis, which provide the necessary foundation for the
impact assessment and interpretation stages of LCA. A clearly defined scope is impor-
tant to identify the intended audience and set the boundaries of the study. The author
discusses practical considerations and approaches for issues commonly encountered
in life cycle inventory modeling (the reader is referred to the ISO 14040 and 14044 stan-
dards for a complete description of LCA methodology). Several important method-
ological issues for creating LCI are discussed, including areas where different choices
can be made depending on the specific systems being studied. This chapter also covers
issues that are the focus of increasing interest in the environmental community, such
as water use and carbon tracking. As LCA evolves, practitioners should stay abreast of
methodological developments, and follow accepted LCI methodology and best prac-
tices when conducting the scoping and inventory stages.
Keywords: Life cycle assessment, life cycle inventory, goal definition, scope

3.1 Introduction

A Life Cycle Assessment (LCA) consists of four phases:

• Goal and scope definition,
• Inventory analysis (LCI),
• Impact assessment (LCIA), and
• Interpretation.

The life cycle inventory (LCI) provides the foundation of the life cycle
assessment (LCA). The inventory of flows to and from the natural environ-
ment serves as the basis for the impact assessment and interpretation phases
of the LCA, so it is critically important that the inventory be methodologically
sound, complete, and unbiased.
International Standards ISO 14040 and 14044 provide detailed guidance on
the key aspects of life cycle inventory methodology [1,2]. This chapter will

Mary Ann Curran (ed.) Life Cycle Assessment Handbook: A Guide for Environmentally
Sustainable Products, (43-66) © 2012 Scrivener Publishing LLC

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