1

Date: August 31, 2011

Subject: Minutes of the August 31, 2011 Meeting with Representatives of the Wool 

Fiberglass Industry and NAIMA

I. Introduction

A meeting with representatives of the North American Insulation Manufacturer’s Association 

(NAIMA) and the wool fiberglass manufacturing industries was held at the U.S. Environmental 

Protection Agency (EPA) facility in Research Triangle Park, NC, on August 31, 2011. The 

purpose of the meeting was to discuss chromium and hexavalent chromium emissions from glass 

melting furnaces at wool fiberglass facilities. This memorandum summarizes the major topics 

discussed during the meeting.

II. Attendees

Steve Aldridge, Knauf Insulation

Lauren Alterman, CertainTeed

Brian Baker, Knauf Insulation

Ken Gould, Owens Corning

Ron Hudson, Johns Manville

Mike Metz, Guardian Fiberglass

Mike Pettis, Owens Corning

Grover Thomas, Guardian Fiberglass

Brent Tracy, Johns Manville

Angus Crane, NAIMA

Christopher Martin, NAIMA

Susan Fairchild, U.S. EPA, OAQPS

Winifred Okoye, U.S. EPA, OGC

Keith Barnett, U.S. EPA, OAQPS

Carlos Davis, CertainTeed

Cindy Hancy, RTI International

Richard Marinshaw, RTI International

III. Discussion

The purpose of this meeting was for EPA to discuss chromium and hexavalent chromium 

emissions from glass melting furnaces with the wool fiberglass industry. The discussion focused 

on the large range of chromium and hexavalent chromium emissions and its relation to chrome 

contents in refractories. Prior to the meeting, NAIMA emailed a handout to participants that would 

be discussed in the meeting, this is included in Attachment 1. 

The initial discussion concerned the composition of chrome refractories. According to NAIMA’s 

handout, chromium contents in furnaces are similar across the industry and do not seem to 

correlate with chromium emissions, which makes it difficult to determine which furnaces have 
2

high chromium emissions. Industry believes that chromium emissions have more to do with the 

furnace type than with the chromium content of the refractory. The following paragraphs highlight 

the discussion on chromium refractories and glass melting furnaces. 

IV. Chromium Refractories

In addition to NAIMA’s handout showing chromium contents of furnaces and emissions, Saint 

Gobain provided further information as to why they do not believe chromium emissions are 

related to chromium contents in refractories. Saint Gobain is one of the primary producers of

chromium refractories in the US, which are used in several industries (insulation glass, container 

glass, and e-glass). Depending on the industry, these refractories contain different amounts of 

chromium. Saint Gobain believes that these industries have similar emissions profiles, which 

shows that chromium refractory content is not directly correlated with chromium emissions. 

Industry believes that chromium emissions are more related to furnace type. NAIMA also stressed 

the economic importance of chromium refractories in the wool fiberglass industry.

V. Glass Melting Furnace Information

After Saint Gobain’s discussion of chromium refractories, an Owens Corning representative 

discussed, in detail, the differences between each furnace type, focusing on oxy-fuel furnaces. 

Industry believes that high chromium emissions are related to oxy-fuel furnaces for the following 

reasons and proposed to subcategorize furnaces by type. 

Oxyfuel Furnace:

• Use the same type of refractories as other furnaces, but contain more “walls” than other 

furnaces. 

• Contain hotter flames and higher melting temperatures. Cause higher oxidation rates of 

chrome. 

• Oxyfuel furnaces also have 90% of chrome refractory above the glass line. 

• Gives less NOx, but higher chrome emissions. 

Participants then discussed the location of chrome refractories with respect to the glass line;

industry stated that all refractory above the glass line is chrome refractory and can equal in 20,000 

lb/yr of refractory losses. Industry also explained that chromium emissions do not necessarily 

come from the glass and refractory contact line. EPA proceeded to ask how furnace age correlates 

to emissions and industry responded that it is not related to chrome emissions because the part of 

the refractory that gets “eaten” away is under the glass line and not exposed to oxidizing air. EPA 

believes this information is contradictory to previous discussions and that they will need more 

information in order to fully understand what exactly is causing some furnace to have high chrome 

emissions. Participants decided that EPA would contact a refractory expert at Clemson University 

and Industry would aid in this process and that industry would supply any additional information 

that would be helpful. 

VI. General Information
3

NAIMA and industry representatives also discussed the phasing out of phenolic binders and 

wanted to know if they would still be “out” of the rule once facilities phased these binders out. 

EPA stated that it is not trying to find new ways to make the subject to the rule, but that chromium 

emissions are both risk and “brick” issues that need to be addressed and subcategorization may or 

may not be possible. Participants discussed possible requirements that could be proposed (i.e., area 

source rule, regulated source definition, source tests, etc.) and the possibility of an extension. EPA 

felt that an extension would be nearly impossible. See also notes from EPA meetings with 

Certainteed from both the project lead, Susan Fairchild, USEPA/OAQPS/SPPD and Hugh 

McCullough, Region 7.