Scoring the Referees: How Pharos Judges Green Labels

[Editor's note: Today's guest post is authored by Bill Walsh, Executive Director of the Healthy Building Network.]

When building products carry different green certifications, how do you know which product is best? Maybe there is a way to compare apples and oranges.

As green certifications and labels have proliferated, so has greenwash. Even among legitimate certifications, conflicts and inconsistency have made them hard to understand.

How do you cut through the cacophony and get the information you want? The Pharos Project has independently organized information on about 48 major product certifications and products that carry those labels.

Start by finding products

If you want products certified to a specific standard, you can find the certification standard you are looking for on Pharos's certifications page or, alternatively, simply type the name of the standard into Pharos's search function. Once on the page for the standard you want, click on the tab labeled "Products with this certification in Pharos" and voila.

But getting a list of similar products with a similar certification sometimes doesn't translate to the real world. What do you do when you facing similar-looking products that carry different certifications?

Weighing products with different certifications

When searching within a product category, the Pharos Building Product Library helps you compare and evaluate products certified under different labels.  Each product record in Pharos documents and displays all of certifications that product has earned. Pharos generates scores for each impact category that account for these certifications. The more rigorous the certification, the higher the Pharos score.

For example, if two resilient flooring products boast two different certifications for indoor air quality, the product meeting the more rigorous standard will receive a higher score for that certification.

And if two products sport the same certification and score in one impact category, Pharos lets you easily take into account other impact categories to further differentiate. For example, it might be important to you to start your Pharos search to include only products that meet a certain VOC emissions standard, and then further refine the search to select for the highest renewable materials content from among those low VOC materials.

Compare certifications

Pharos helps you learn more about how the certifications compare in their rigor and what issues they cover, The certifications can be browsed as a complete list, browsed by category (Biobased, Recycled Content, etc.), or searched by name or certifying organization. Certifications can then be sorted by how they score in Pharos impact categories to give you an immediate comparison of which certifications are the most rigorous.

Each certification's detailed view includes a description, the Pharos score it earns, an explanation of how the certification impacts product scoring, direct links for more information, and a link to view a list of products in the Pharos Building Product Library claiming that certification. Pharos team tools allow subscribers to add personal or company tags to certifications to enable easy saving and sharing.

Behind the curtain: How our scoring works

Understanding how Pharos scores the certifications can help you understand how those certifications work. We start by looking at how the attributes that the certification is addressing and thresholds of performance it certifies compare against the Pharos ideal in a given category (the ideal of zero VOC emissions for the VOC score category, for example) and the benchmarks (in our 1–10 scoring framework) that we have established on the way to that ideal. Comparing different certification standards against a standard measure helps you better compare them.

We also examine the administration of the certification. An ideal certification is administered by an independent third party that manages the sample selection and chain of custody (getting the right sample quickly to the testing lab), and makes the determination of whether the product meets the standard.

Manufacturer claims can be considered rigorous if they are regularly audited by a governmental body (such as the California Air Resources Board, or CARB, in the case of formaldehyde regulations). Pharos drops certifications one point in score if they are administered by an interested or potentially biased party, the most common being a trade association (for example, the Carpet and Rug Institute's GreenLabel Plus) or if the claims are certified by an independent lab but the manufacturer does the sample selection.

No perfect 10 for VOCs--content or emissions

You many notice that no certification scores a perfect 10 in VOC emissions yet. The Pharos ideal in this category is an independent third-party certification with no detection of VOCs. You may be surprised to learn that no certifier yet offers this. They all certify to a variety of thresholds for acceptable VOC emissions.

Some products do indeed have zero VOC emissions and a manufacturer can document a claim of zero VOC emissions through a lab report but as described above, this report can only score a 9 because it is not certified by a third party.

You also might notice that no VOC content certifications get even close to a 10--why? Two reasons: First a number of known VOCs are exempted from most certification standards--why? Because most VOC certifications are based upon VOC regulations that reference the VOC's contribution to ozone smog. They were designed to combat outdoor air pollution, not to guarantee indoor air quality.  Thus, the common "definition" of a VOC is a political one, not a scientific one. This definition misses a number of important VOCs.

While the certifications have some catching up to do here, Pharos accounts for a greater number of actual VOCs and provides a higher score if full content disclosure from the manufacturer reveals no exempt VOCs.

The second reason is that some non VOC chemicals in wet applied products can actually create new VOCs in the curing process. So regardless of content, emissions testing is needed to insure that a product is not releasing VOCs.

As you can imagine there are even more surprises and conundrums that we encounter in all 48 certifications analyzed by Pharos. So head to the Pharos website, dive in, and be sure to share any ideas you have for refining or improving our analysis!