From The Smokestack To Your Floor – Post Consumer Fly Ash?

Tom Lent | October 24, 2012 | Policies

*** Nov. 20, 2012 update:  NSF International Retracts Post-Consumer Fly Ash Designation. Click here to read. ***

Should fly ash from coal fired power plants be considered post-consumer recycled material?  Amazingly, NSF International, the certification and standards institution, thinks so.  Two recent decisions added fuel to the debate about the use of coal-fired power plant waste in building materials:  First, NSF designated “Celceram” -- coal fly ash marketed by Boral Material Technologies -- as a 100% post-consumer product.  Then, by a 14-4 vote, an NSF Standards Committee decided to eliminate language from the carpet sustainability standard, NSF-140, that defines fly ash as pre-consumer content only. [1]

Widely used in carpet backing, fly ash products such as Boral’s Celceram are the byproduct of burning coal. EPA is investigating concerns about coal ash. A 2010 EPA study of Metals in Air Pollution Control Residues from Coal-Fired Power Plants subjected fly ash and FGD (flue gas desulferization) residue samples from 34 different coal fired power plants to multi point leachate tests. The study found that significant numbers of samples exceeded a variety of regulatory toxicity thresholds for heavy metals such as arsenic, barium, chromium and selenium and concluded that the standard single point tests frequently used in the industry are of lmited value.

After years of vigorous promotion of the “beneficial use” of fly ash as a recycled material, EPA has more recently struggled with how best to regulate this hazardous waste material, caught between fly ash’s massive disposal problems and continuing concerns about lifecycle problems from dispersing the toxic heavy metals in building products.

Fly ash has long been considered a pre-consumer (post-industrial) recycled material. The NSF decision to accept Boral’s post-consumer claim is a high stakes one, doubling the value of the recycled content in the LEED rating system [2] and opening the door to higher ratings in NSF 140 [3]. Fly ash companies apparently unsuccessfully approached several certifier organizations with the claim before finding NSF willing.

Representatives of several other certifying bodies I interviewed for this story were unanimous in condemning the NSF decision, noting that fly ash is a byproduct of an industrial process and should not count as a post-consumer product any more than the shavings from a milling operation would be considered post-consumer.  

Wes Sullens, Program Manager in the Green Building group of StopWaste.Org, calls the application of the term ‘post-consumer’ to fly ash “incongruous,” noting that a post-consumer claim is intended to be used where products go to market, are used directly by consumers, and then collected for recycling. Everyone I interviewed for this story felt that the ISO standard (ISO 14021) is pretty clear that material diverted from the waste stream during a manufacturing process is pre-consumer material.

A representative of a major carpet company, although currently using fly ash in their backings, worries that this designation will actually create a disincentive to use higher-value recycled content streams – namely the old carpet that the industry has struggled to reclaim. The manufacturer, for now, has decided not to adopt the post-consumer designation in their product specs despite the gain they could realize in LEED credits.

We strongly agree and encourage other manufacturers to follow suit and leave fly ash designated as pre-consumer recycled content. We think this fly ash post-consumer designation damages the credibility of recycled content claims and the NSF 140 program. These decisions open the door to all sorts of power plant wastes, from solid waste incinerator ash to spent fuel rods. By the NSF’s logic, any of these wastes could be defined as “post-consumer” material.

We also encourage the USGBC to reject this claim and use this opportunity to clarify the definition of post-consumer recycled content. Meanwhile, specifiers will need to scrutinize post-consumer recycled content claims more carefully to avoid this kind of greenwash, even if third party certified.

The fly ash post-consumer debate comes at an interesting time just as the USGBC has released the latest public comment version of LEED V4 with significant new material credits that address toxic content and that highlight responsible sourcing of raw materials. The sourcing credits start to put the kind of spotlight on the impacts of agricultural and mining practices that the FSC credit has long put on forestry practices. Maybe it is also time to take a close look at the sustainability of recycling practices and adjust certifications and rating systems to incent those products that facilitate true closed loop recycling and avoid the production and recirculation of toxic materials.  

(revised 12/11/12 to reference and explain an EPA study)


[1] The committee struck this sentence:  “Coal fly ash used as a filler or binding agent qualifies as post-industrial/pre-consumer content only, as do other post-industrial/pre-consumer fillers and binders” replacing it with:  “The determination of post-industrial/pre-consumer or post-consumer content shall comply with an existing recognized national or international standard definition.”

[2] Pre-consumer recycled content is worth only 50% of the value of post-consumer content in LEED Material credits.

[3] This opens the door for any carpet manufacturer to use fly ash to achieve the NSF-140 standard Platinum rating.