3 myths about product life cycle assessments
3 myths about product life cycle assessments
Depending on what you read in the green building press right now, you could be left with the impression that life cycle assessment (LCA) is either the next big thing or fatally flawed and missing key criteria for evaluating green building products.
On one hand, the major overhaul of the Leadership in Energy and Environmental Design (LEED v4) standard, due out in November, will write LCA into the world's dominant green building standard at both the building and product level. On the other hand, green building advocates have been quick to critique the ease with which LCA can be used for greenwashing, the questionable quality of the data it generates and its failure to include life cycle toxicity impacts.
As a building products company that has used LCA since 2000, Interface has a strong interest in having LCA understood and applied correctly. Like most companies who employ LCA, we have used it first and foremost as an internal tool in R&D for evaluating proposed changes to our processes and materials.
From its origins as a tool to help companies understand resource use during the oil crisis of the 1970s, LCA has evolved into a serious academic discipline, with peer reviewed papers, academic journals and professional accreditation. Today, LCA is a powerful tool for understanding the full life cycle (cradle-to-grave) environmental impacts of our decisions, both for companies and for consumers, but only if it is used correctly.
"LCA doesn't do everything, but it does the things it's intended to do very well," says Connie Hensler, our global director of LCA programs and a certified LCA professional.
With LCA being built into everything from LEED to the Good Guide and Walmart Sustainability Index, it is in all of our interests to understand a bit more about what we're looking at. Here are three persistent myths about LCA. There is a grain of truth in each, but also a fundamental misunderstanding.
Magnifying glass image by Laborant via Shutterstock.
Myth No. 1: Greenwash
"LCA can be used to justify anything, so manufacturer-sponsored product comparisons are nothing but greenwash."
The grain of truth: LCA has been misused by manufacturers to support environmental claims. A famous example of this was an LCA duel in the washroom between a manufacturer of electric hand driers and the paper industry. Each study professed to measure objectively whether using the hand drier or paper towels had a higher life cycle environmental impact. Perhaps needless to say, the hand drier company found their product to be superior and the paper industry found paper towels to be the clear environmental winner. As is always the case with LCA, the devil is in the assumptions. The hand drier study, for example, assumed the use of multiple paper towels after each hand washing. On the flip side, the paper towel study certainly did not assume the hand drier was powered by photovoltaics.
The misunderstanding: When LCA is only used for internal comparisons, it is no problem to hold assumptions constant. As LCA emerged as a tool for product comparisons, new standards had to emerge in lockstep. ISO 14025 and 14040 now standardize the practices and assumptions underlying LCA calculations. Manufacturers now can have a third party verify that their product LCAs followed the ISO standards and the relevant product category rules (standard assumptions) to create an environmental product declarations (EPD). The product category rules for floor coverings used to create EPDs for all of our product lines explicitly state, for example, that any adhesives used to install the product also must be included in the calculations. This is the kind of thing the self-serving LCAs of the past conveniently might have forgotten to include. With multiple manufacturers publishing third party-verified EPDs, meaningful "apples-to-apples" comparisons amongst product LCAs can be made in many building product categories.
Myth No. 2: Data
"The lack of accurate data available makes LCA meaningless."
The grain of truth: Much of the data in an LCA is calculated, not collected from observations of a product's actual life cycle.
The misunderstanding: LCA should be understood as a rigorous scientific modeling exercise, not a comprehensive accounting of the exact environmental impacts that have happened or will happen during a product's life cycle. For instance, while the numbers in our EPDs tap actual energy use data from our own factory's utility bills, the amount of carbon dioxide emitted during the extraction and refinement of the raw materials needed to make our products must be modeled using the best available scientific estimates and industry data (professional caliber software tools have made this easier). But this does not at all diminish the usefulness of LCA, especially as a source of strategic insight about a product's impact "hot spots." For example, LCA showed us that the impacts of producing our carpet backing were small relative to the impacts of producing virgin nylon yarn from oil. This led to years of work with our suppliers to produce the first high post-consumer content nylon yarns, which has done more than anything else to shrink the footprint of our products. In a hypothetical Big Data future, we all may have full access to real time data about our supply chain impacts, but in the meantime, LCA modeling allows us to take responsibility for the parts of our footprint we don't see everyday.
Myth No. 3: Toxicity
"LCA results are misleading because they fail to include life cycle toxicity impacts."
The grain of truth: While standardized LCA metrics for human toxicity and eco-toxicity have been developed and are being improved, they are not yet accepted within the mainstream of LCA practice because of how inexact and uncertain they are to model. Trying to turn the already uncertain world of chemical risk and hazard assessment into a single number for all of the ingredients, process chemicals and byproducts used in a product's life cycle remains a bridge too far for LCA.
The misunderstanding: Criticizing LCA for not addressing toxicity (or social justice, for that matter) is like criticizing penicillin for how poorly it works against viruses; LCA doesn't do everything and simply was not designed to address these difficult-to-quantify impact areas. Typically, LCA impact categories are limited to climate change, smog, ozone layer depletion, acid rain, water use, non-renewable resource use and water pollution (eutrophication), which certainly have direct and indirect impacts on human health. But if you want to assess categories such as toxicity, social impact and biodiversity loss, you need a different tool. New tools are emerging to address the gaps in LCA, including the health product declaration, which expands upon the ingredients disclosure required by most EPDs, and adds chemical hazard warnings for each ingredient.
A final word
Despite the understandable excitement around EPDs and LCA-based product scorecards, we should remember that the ultimate goal of LCA is not comparison, but improvement.
It "is not about determining if a product is 'green' or not, but about quantifying impacts and seeing if, how and where we can improve," LCA firm PE International says in a recent report.
There may come a day when we have the ability to exactly quantify every possible dimension of sustainability with a single tool, but until then, we are confident that LCA can keep us moving in the right direction on our journey. If we contribute to a few more LEED credits along the way, that's not a bad thing, either.