# Ferguson, Andors & Company

P.O.Box 678, South Royalton, VT 05068 • 802- 763-2339 / 802-419-3799 Fax • facomail@sover.net

Consultants in Product Development and Regulatory Compliance April 30, 2010

Mr. Gil Wood Environmental Engineer U.S. Environmental Protection Agency Office of Air Quality Pla nning & Standards (C404-05)

109 T.W. Alexander Drive Research Triangle Park, NC 27709

Re: Enhanced Certified Wood Heater Database

Dear Mr. Wood,

This letter will provide background information re garding the Enhanced Certified Wood Heater Database (the “Database”) that the Heart h, Patio and Barbecue Association (“HPBA) has complied and provided to EPA and stakeholders interested in EPA’s ongoing review of the New Source Performance Standard (“NSPS”) for Resi dential Wood Heaters (40 CFR Part 60, Subpart AAA), As you are aware, HPBA is the principal trade association repres enting the interests of manufacturers, distributors and retailers of wood heater s and other hearth a ppliances. HPBA has a longstanding cooperative relationship with EPA and state regulatory aut horities regarding the regulation of hearth appliances; one of the highlights of this relationship is the regulatory negotiation that resulted in the promulgation of Subpart AAA more than twenty years ago. HPBA undertook the Database project in the sprit of that longstanding co operative relationship.

The Database project was undertaken to address se veral obstacles that sto od in the way of using data available to EPA on certified wood heater perf ormance. First, the li st of certified wood and pellet heaters posted on the EPA website lists many heater models as separate models that are actually the same model, as we ll as many that are no longer bei ng produced. This has occurred for several reasons including company consolidati on within the industry as well as certifications

that are still in effect from models that have ceased production or been replaced by updated

versions with new certifications. If the certificat ion for a previous model version hadn’t lapsed,

the older model and newer model could both be on the certified heater list. In other cases, companies with certified heater models have s imply gone out of business. Addressing these issues implicated contacting the manufacturers directly, something HPBA was well positioned to do, since most of the manufacturers are HPBA members. Second, once a correct list of the current universe of certified appliances was asse mbled, it would be necess ary to match that list with the certification test reports applicable to e ach model. Those data ar e available, of course, in EPA’s files, but the test repo rts and certification data are not in electronic format. Each test report therefore would need to be examined by hand to extract and extract and compile the

needed information. This would have to be done by EPA and would be a major undertaking.

HPBA formulated a methodology to assemble a useab le database, that had as its objectives the culling of the EPA certified heater list down to those heater models th at are currently in production, and obtaining detailed certification test data and ot her information that might be useful in the NSPS process and that was not included on the EPA website (e.g., the test method

used for certification testi ng for each heater model).Mr. Gil Wood April 30, 2010

Page 2 of 3 First, a list of manufacturers /importers of certified wood and pellet heater manufacturers was generated from the EPA certified heater list. The list was then examined and corrected to reflect situations where company consolidation had occu rred. Finally, every possi ble effort was made to obtain up-to-date contact information for each comp any on the list. It s hould be noted that in some cases, generally for very small or forei gn companies, reliable contact information was simply not obtainable.

Second, each manufacturer/importer was sent a form listing each of the cer tified heater models attributed to their company. They were asked to first eliminate obsolete models from their list and then to provide detailed info rmation about their currently pr oduced certified models. This

information included emission data from certification testing, id entification of the test method used for certification and the certification expi ration date. To protec t confidentiality, HPBA assigned the responsibility of receiving and compili ng the data to their in -house statistician. As the data arrived, he assigned a model number desi gnation to each dataset in the order received. He created a key that would allow only him to know what the actual model and manufacturer identity was. This is similar to the process used for gathering othe r industry statistics (sales data, for example) where confidentiality needs to be maintained.

As data started to arrive, it beca me apparent that some of the in formation that was being received was incomplete or had potential data quality issues. Additional contact was made with the manufacturers to try to improve the data that was be ing received. In some cases, the follow-up

was successful and in other cases it was not.

As a means to insure the quality of the data submissions, an emission data quality check was performed for each heater model. This pro cedure was to calculate the weighted average emissions in accordance with EPA Method 28, Secti on 8.1 using the certification test data that were received and comparing the calculated value to the weighted average emissions listed for the model by EPA. When discrepancies that were outside of the realm of rounding errors (usually 0.1 gram/hour) were detect ed, the datasets were labeled as having data quality problems.

HPBA went back to those manuf acturers/importers yet again, to try to resolve the data quality issues. Again, there were some successes and some failures to resolve the issues. If we could not resolve the data quality i ssues, that fact was noted for the affected models. See the discussion of data “color-coding” below. And it s hould be noted that generally, the datasets with quality issues were distributed at the higher emission rates.

There were two releases of the Database. Th e first, in December 2009, included datasets that

had issues that had not been re solved as of the release date . A color-coding system was employed to identify those datasets with suspec t data, duplicate data or missing data Known fan

confirmation test runs were also identified. The Database worksheets included a color-code key at the top to help the users. As explained on those worksheets, data that was suspect was coded green. Generally, suspect data we re any datasets that were rece ived that did not result in the EPA published weighted average emissions when the data quality check was made. Duplicate data was coded orange. Duplication of data wa s noted when the manufacturer reported multiple models that had been approved using the same certi fication test. This occurs when the same core design (“engine”) has different aesthetic “bodie s” available with different model numbers, forMr. Gil Wood April 30, 2010

Page 3 of 3 example. Data sets with missing data were code d yellow. HPBA continued to work to resolve these data issues with additional manufacturer follow-ups until it had to finally conclude those activities due to diminishing retu rns relative to the re sources being used. The second (and final)

version of the Database was re leased in February 2010. Again, a similar color-coding system

was used to differentiate usable data from unusab le data with additional color-coding (pink) used to identify where new or corrected data or information had been received and included. The second version also noted where model lines, origin ally thought to be in current production, were actually in the obsolete category. These were coded in gray. Again, a color coding key was provided at the top of the worksheets to guide the users. The first tab on the Excel worksheet includes all data received, regardless of its qua lity. The second tab on the worksheet, labeled “Full Usable Data Final 2.25.10” only includes th e datasets where the quality of the emission data for each dataset has been confirmed by the qua lity check calculation. Datasets that didn’t pass the QA were excluded from the compilation unde r this tab. Duplicate datasets and obsolete

models also were excluded. This is the databa se that should be used for any analyses that are

undertaken. The fact that some of these datasets do not include identification of the test method used reduces the usefulness of those particular da tasets for determination of best demonstrated technology but they may still be useful for othe r purposes (such as evaluating data weighting schemes and the implications of va rying the number of test runs).

The final overall result was usab le datasets for 15 catalytic wood heaters, 110 non-catalytic wood heaters and 22 pellet heaters. Elimination of th e datasets without the te st method identification resulted in a final tally of 15 catalytic wood heaters, 86 non-catalytic wood heaters and 17 pellet

heaters.

The information in this letter was prepared by Robert Ferguson of Ferguson, Andors & Company

at the direction of the Heart h, Patio and Barbecue Association. Ferguson, Andors & Company is providing technical consulting serv ices to HPBA. Please contact me if you have any questions concerning the methodology used to compile the Database, or need any additional information about it. HPBA looks forward to working with you and your staff as EPA moves forward to complete its review of Subpart AAA.

Respectfully submitted,

Robert W. Ferguson Ferguson, Andors & Company Consultant for the Hearth, Patio & Barbecue Association