Green Guide to Green Build - Advancing Use of LCAs: Product Life Cycle Assessments
WHAT THEY AREProduct Life Cycle Assessments (LCAs) offer architects and interior designers the most complete and scientifically robust information on a product's exchanges with the environment throughout its life-cycle-that is, from raw materials sourcing, transportation of materials to the manufacturer's facility, through manufacturing processes, shipping and end-of-product-life disposal or re-use.
A full LCA (as compared with streamlined) needs to be conducted in alignment with the International Standards Organization (ISO) Standard 14044 to provide the greatest value; for this provides assurance that data collection, analysis and assessment processes are transparent and are used internationally as accepted LCA methodology. Doing so increases the reliability of comparisons.
WHAT THEY DODevelopers of LCA tools begin with creating Product Criteria Rules (PCRs) for each product category. Commercial carpet tile, for example, is a product category that can establish what data is to be collected by all manufacturers providing brand product LCAs and in what units the data is to be submitted to a reviewer as a Life Cycle Inventory (LCI). For the resulting product LCA to be distributed publicly as an ISO-compliant LCA, the LCI must be certified by a third-party professional LCA Practitioner. Once that is done, the LCA Practitioner converts the product data (submitted in the form of mass weights or economic units) into environmental impacts, generally using the 12 impacts identified by the U.S. Environmental Protection Agency (EPA's) Science Advisory Board. THE 12 IMPACTS ARE:1. Global warming5. Indoor air quality9. Ecological toxicity2. Acidification6. Habitat alteration10. Human health3. Eutrophication7. Water intake11. Ozone depletion4. Fossil fuel depletion8. Criteria air pollutants12. SmogThe conversion from mass weights into environmental impacts is generally conducted using the TRACI software developed by the EPA. TRACI is an acronym that stands for Tools for the Reduction and Assessment of Chemicals and other Environmental Impacts.
HOW THEY'RE USEDWhen the underlying data and the results have been certified by an LCA Practitioner, they can be used in various ways:
- By the manufacturer internally to engage in DfE (Design for the Environment) development of a new product or redesign of an earlier product.
- By the manufacturer to complete an application to certify that one of its brand products has met the Registered, Silver, Gold or Platinum level of a particular Product Standard (see sidebar on Product Standards for examples).
- By a certifying body offering specifiers and purchasers an opportunity to review many product LCAs and compare their results efficiently.
- By a certifying body to complete a certified Environmental Product Declaration (EPD)-integrating various types of product performances for purchasers.
- By specifiers and purchasers to provide documentation as to why they have selected one product type or brand over a number of alternatives.
As there are three user groups for LCA tools, there are, understandably, three different kinds of LCA software programs. All rely on the ISO Standard for LCA.
The first group of LCA tools consists of software developed for use primarily by the LCA Practitioner and requires a detailed understanding of LCA methodology and is used for many different types of products. Professionals engaged full time in developing Product LCAs as staff or consultants to manufacturers use these tools to produce in-depth analyses of a product's exchanges with the environment over its full life-cycle with a focus on chemicals and their emissions.
The second group of LCA tools features software developed for use primarily by product designers, product managers and other staff members in manufacturing firms. Generally, they are scientists, often with backgrounds in chemical engineering, but are not LCA Practitioners. These professionals use LCA software to conduct internal
"what if" scenarios while designing or redesigning a product line in order to see how alternative materials, manufacturing processes, packaging, transportation and end-of-product-life decisions affect a product's footprint. Later, they use the product LCA results to apply for certification of a brand product to a Sustainable Product Standard and/or to communicate a product's footprint to the marketplace.
The third group of LCA tools serves building designers, primarily by featuring product LCA summary results. Unlike the tools in the first two groups, these tools do not show the data in mass weights or economic units; instead, they feature environmental impacts, shown impact by impact, as well as aggregated impacts. They are a response to demands from the A&D community to make product LCAs designer-friendly while retaining scientific robustness.
As architects and interior designers are not required to study the data analyses behind the summary results, they must be able to believe in the credibility of the source-relying on their professionalism, their peer review of data, etc., as well as the credibility of the processes used, including their alignment with the ISO Standard for LCA.
While building designers do not have to see or even fully understand the data used, they do have to trust the product LCA results. This trust can be most easily established with a product LCA meeting the ISO Standard as it offers architects and interior designers the assurance that the underlying data has been developed using a methodology that meets standards developed by scientists and accepted by many national and international entities.