UNITEDSTATESENVIRONMENTALPROTECTION AGENCY Offtce ofAIMQuality Planning and Standards Research Triangle Park, North Carolina 2771 1



### FEB231990

MEMORANDUM

SUBJECT: Summary of Crested Butte WoodHeater Study -Preliminary

FROM: William G. Laxton, Director

Technical Support Division (MD

TO: Distribution List

Attached to this memorandum is asummary of the preliminary findings from the emission test program designed to evaluate the in-home test method to be applied in Crested Butte, Colorado. The purpose of this distribution is to alert you to several important indications resulting from these tests. The EPAprogram had two objectives: (1) to evaluate the Virginia Polytechnic Institute (VPI) in-home sampler relative to the EPAcertification test method, and (2) to determine the effect of high altitude or low barometric pressure on wood heater emissions. The test series provided the following:

a. the relationship between the measurements of the VP1method and the EPAMethod 56was linear over the range of emissions from 1to 

### 35g/hr;

b. the altitude effect onwood heater particulate emissions wasnot significant for the catalytic woodstove but mayhave been significant (about 25percent at 8900 ft elevation) for the noncatalytic unit although the results were within the range of low altitude results bythe accredited laboratories;

C. the emissions from both the noncatalytic and the catalytic stoves increased about 7g/hr from the certification test to the simulated in-home operation; and

d. the Ashley stove, representing the type of unit being replaced in the Crested Butte homes, produced about twice the emissions produced by acertified noncatalytic wood heater -the Haugh's stove.

The final report from the contractor is due in March andwill include Colorado emission data in addition to the verified particulate emission results.

If you have any questions about the test program or the results, contact Dennis Holzschuh (919) 541-5239 or Peter Westlin (919) 

### 541-1059.

Attachments (2)DISTRIBUTION

EPAReoional Air Divisions:

Louis F. Gitto, Director Air, Pesticides and Toxics Management Division JFK Federal Bldg. Boston, MA 02203-2211

Conrad Simon, Director Air &Waste Management Division 26 Federal Plaza NewYork, NY 10278

Thomas J. Maslany, Director Air Management Division 841 Chestnut Building Philadelphia, PA 

### 19107

Winston A. Smith, Director Air, Pesticides, &Toxics Management Division 345 Courtland Street, NE Atlanta, GA 30365

David Kee, Director Air &Radiation Division 230South Dearborn Street Chicago, IL 60604
Regional Environmental Services Division

Edward 

### J. Conley, Director Region 

### I (EAA-LEX) NewEngland Regional Laboratory 60Westview Street Lexington, MA 02173

Barbara Metzger, Director Region 

### II (ES/Bldg. 

### 10) Woodbridge Avenue Edison, 

### NJ 08817

Greene A. Jones, Director Region 

### III (3ESOO) 841 Chestnut Building Philadelphia, PA19107 BobHanneschlager, Acting Director Air, Pesticides, &Toxics Div. 1445 RossAvenue Dallas, TX 

### 25202-2733

William A. Spratlin, Director Air &Toxics Division 726 Minnesota Avenue Kansas City, KS 66101

Irwin L. Dickstein, Director Air &Toxics Division 999 18th Street Denver Place -Suite 500 Denver, CO 80202-2405

David P. Howekamp, Director Air &Toxics Division 215 Fremont Street San Francisco, CA 

### 94105
Lyn McKee, Acting Director Air &Toxics Division 1200 Sixth Avenue Seattle, WA

### 98101

James H. Finger, Director Region 

### IV College Station Road Athens, GA 30613

William H. Sanders, 

### III, Director Region V(5s) 536 South Clark Street Chicago, 

### IL 60605

Russell F. Rhoades, Director Region 

### VI (6E) 1445 RossAvenue Dallas, TX 

### 75202-2733DISTRIBUTION (continued)

Billy Fairless, Director Region VII 25 Funston Road Kansas City, KS 66115

James B. Lehr, Director Region VIII 999 18th Street Denver Place -Suite 500 Denver, CO 80202-2405 Terry L. Stumph, Chief Environmental Services Branch Region XI 215 Fremont Street San Francisco, CA 94105

Robert G. Courson, Director Region X(ES-096) 1200 Sixth Avenue Seattle, WA 98101UNITED STATES ENVIRONMENTAL PROTECTION AGENCY Office ofAir Quality Planning and Standards Research Triangle Park, North Carolina 2771 1

MEMORANDUM

SUBJECT: Summary of Preliminary Data Comparing Certification and In-home

WoodHeater Emission Test Methods

FROM: Dennis Holzschuh, FTS(MD-l4m&qL

Peter Westlin, TSS(MD-19)

TO: Gilbert H. Wood, Chief

Emission Measurement Branch (MD-14)

Introduction

The Emission Measurement Branch recently completed anevaluation of the field test method proposed for the Crested Butte, COwood heater replacement and emission reduction program. Theevaluation was undertaken in cooperation with the Air and Energy Engineering Research Laboratory, EPARegion 8, Colorado Department of Health, the WoodHeating Alliance, and the Crested Butte city council. Theobjectives of the method evaluation program were:

1. Evaluate the in-home emission sampler developed bythe Virginia Polytechnic Institute (VPI) Mechanical Engineering Department and develop anempirical relationship between the measurements from the VP1sampler and EPAMethod 56 used for certifying woodheaters; and

2. Determine the effect of high altitude (low barometric pressure) on wood heater emissions.
Summary of Program

The test program wasconducted in three phases. The first phase wasto become familiar with the VP1sampler and measurement procedure. Dennis Jaasma of VPI provided several sets of sampling equipment and on-site instruction on the operation, sample recovery and analysis, and calculation of results. EPA and the contractor, Engineering Science (ES), reviewed the procedure and developed an improved protocol for the laboratory andfield testing portions of the program.

The second phase wasto compare the VP1and Method 56under conditions simulating certification testing. Twostoves, the Sweet HomeAK-18 catalytic model and the Country Comfort CC-150 noncatalytic unit, were selected because they had been tested extensively during the EPAlaboratory accreditation

### 2

program. Somemodifications to the stove operation prescribed for certification tests were necessary to accommodate operation of the VP1method. These modifications included repeating wood loadings to extend the operating time. The laboratory tests were completed at ES's RTPlaboratory.

The third phase involved additional comparison tests at 9000 ft altitude. Twomore wood stoves were added to the testing program to obtain emission data for stoves typical of those being replaced and those to be installed in Crested 

### Butte. The testing included two types of stove operation: 

### (1) simulated certification test conditions for the AK-18 and the CC-150 stoves, and (2) cord wood operation at arange of burn rates simulating in-home conditions for all four stoves. During the cord wood, -/-day tests, the VP1sampler wasoperated at the low flow rate modeaswould beapplied in the in-home studv. Durinq the sameperiod, the Method 56train wasoperated of the seven daily Method 56 lue for the samestove operating and recovered on"a dailv basis. The'average ingle va results were compared w:th the VP1s period.
Summary of Results

Both the VP1andthe Method 56trains were operated in pairs during the simulated certification testing sothat between train or method precision could bedetermined. Experience with wood heater test methods indicates that method precision is onthe order of 0.5 g/hr. Results of these comparisons will bediscussed in the final report to be prepared by ES. The results discussed below concentrate onthe comparison of the two methods and the altitude factor and are preliminary pending completion of the final report and EMBreview.

The attached table provides asummary of the average emission results for 34comparison tests representing over 150 sample train values. Thedata on the table are grouped by stove model with designations for location of the test andthe wood loading configuration. Thetable also provides the average burn rate and emission rates for both sampling methods for each comparison test. The Method 56data include corrections to Method 5Hequivalent values
asspecified in the wood stove NSPS. Theemission rate values represent averages of paired train results. Someof our observations about these preliminary results are asfollows:



### 1. The relationship between the results of the VP1method and Method 56 is nearly linear. The VP1method consistently produced anemission value greater than the corresponding Method 56result. Thecause for this difference wasnot explored during this test program but maybedue to the extra condensing cell in the VP1sampling train andthe lower sampling flow rate, both of which allow for additional condensation to occur. A regression analysis of the emission data from all four stoves at both testing facilities produced the equation:VPIC =0,72(VPIa) +0.96 (all data) (r2 =0.98)

where: VPIC =VP1emission measurement adjusted to Method 56

equivalent, g/hr;



### VPIa =Measured VP1emission value, g/hr. r2 =Measure of correlation, perfect =

### 1.0

Similar ly developed equations for the two locations separately are:

VPIC =0.74(VPIa) +0.91 (RTP) (r2 =0.97)

VPIC =0.72(VPIa) t 0.74 (Crested Butte) (r2 =0.97)

Ouropinion is that these relationships are the samewithin the precision of the methods. Werecommend that the first relationship described above be used to convert VP1emission data to Method 56equivalent values. 3

2. Thealtitude difference had noapparent effect onemissions for these tests. Theonly data comparison that indicated the possibility of asignificant altitude effect onemission rate was the pair of simulated certification test weighted averages for the CC-150 stove. For the simulated certification tests, the CC-150 produced anaverage of 15.9 g/hr at the RTPlaboratory 

### and20.1 g/hr at the Crested Butte facility based onthe Method 56 results. These two results indicated about a25percent increase in emissions from the RTPsite to the Crested Butte location, which is over 8500 ft elevation difference; however, these values fall very nearly within the 11.5 to 20.0 g/hr range reported bythe accredited laboratories. All of the accredited laboratories are at 500 ft or lower elevation. Themodifications to the loading procedure required to accommodate the minimum VP1sampling time mayhave contributed to the slight increase in emissions from the simulated certification tests over the round robin results.

Theweighted average emission rates for the AK-18 simulated certification tests showed agreement between the two locations and with results of previous certification tests. TheAK-18 hadweighted average emission rates of 2.0 g/hr at the RTPlaboratory and 2.2 g/hr at the Crested Butte facility. The weighted average emission rates ranged from 1.5 to 3.5 g/hr under the EPA round robin testing. Clearly, the emission values produced were within the expected range for the certification tests indicating noaltitude effect. (Note: one test run at the RTPlaboratory wasconducted during anapparent failure to achieve catalyst ignition. The results (emission rate =16.0 g/hr) for this test run were omitted from the analysis in order to compare emission tests conducted under similar circumstances.)

3. Theemission test results collected during simulated in-home operation of the CC-150 at Crested Butte showed upto 7g/hr increase in emissions over the average simulated certification test result. The simulated in-home operation of the CC-150 was4

conducted at the Crested Butte facility over at least 7consecutive days for each test. Sampling occurred over periods of low and high burn rates, fuel loadings when the door wasopen, and variations in wood quality. The average Method 56emission rates for the two test runs onthe CC-150 during simulated in-home operation at Crested Butte were 20.8 and 22.8 g/hr compared to the simulated certification test result of 15.9 to 20.1 g/hr.

Onesample with the VP1sampler wascollected for the entire 7-day period. Daily Method 56samples were collected and the seven values were averaged for comparison with the VP1result. The two methods were operated simultaneously sothat the times of stove operation represented bythe two methods were identical. Thecomparable VP1sampler results corrected according to the linear equation described above were 23.7 and 24.0 g/hr.

4. Theemission test results collected during the in-home operation of the AK-18 were 7to 10g/hr greater than those measured during the simulated certification tests. The average Method 56emission rates for the two test runs onthe AK-18 during the simulated in-home operation were 9.2 and 12.4 g/hr compared with the certification test values of 2.0 and 2.2 g/hr. These higher emissions during simulated in-home operation indicate periods of catalyst bypass for fuel loading and start-up and periods of low burn rate which inhibited catalyst ignition.

The corrected VP1emission numbers during the sameperiod were 8.8 and 13.0 g/hr.

5. Theemissions from the Ashley stove were about twice that of the Haugh's stove during simulated in-home operation. The average emission rates measured with Method 56for the Ashley and the Haugh's stove were 30.7 and 14.4 g/hr, respectively.
Engineering Science is preparing afinal report of the testing onthis project including COemission values and paired-train comparisons not included in this preliminary summary. I believe that this information will be useful to anumber of interested parties including the Stationary Source Compliance Division, Air Quality Management Division, Standards Development Branch, Colorado Department of Health, the WoodHeating Alliance, the Air and Energy Engineering Research Laboratory and the manyState and local air pollution control agencies whoare considering woodstove control programs. Weshould distribute this information to these parties.

Attachment

cc: Robert Ajax, ESD Rick Colyer, ESD William Laxton, TSD Robert Lebens, SSCD EdMcCarley, EMB Robert McCrillis, AEERL TomPace, AQMD Jeff Telander, ESDMETHOD AND ALTITUDE COMPARISON TESTS RTP AN0 CRESTED BUTTE, CO

STOVE/ 

### LOADING AVG BURN AVG EMIS RATES 

### LOCATION CONFIG. RATE M5G 

### VP1 (kg/hr 1 (why 1 (g/hr ) -c------------------_I__________________---------- CC-lSO/RTP CC-lSO/RTP CC-lSO/RTP CC-150/RTP CC-lSO/RTP CC-lSO/RTP CC-lSO/RTP CC-lSO/RTP CC-lSO/CRSTD BT CC-lSO/CRSTO 8T CC-lSO/CRSTO BT CC-lSO/CRSTD BT CC-lSO/CRSTD BT 

### CC-lSO/CRSTO BT

AK-1WRTP 

### AK-18/RTP AK-18/RTP AK-18/RTP AK-18/RTP AK-18/RTP AK-18/RTP AK-18/RTP AK-18/CRSTD BT AK-18/CRSTO 8T AK-18/CRSTD BT AK-18/CRSTD BT AK-18/CRSTO BT AK-18/CRSTD BT

HAUGHWCRSTD BT HAUGHS’CRSTD BT HAUGHS/CRSTD BT

ASHLEYXRSTD BT ASHLEY/CRSTD BT ASHLEY/CRSTO BT

Note : “CC-150 I#

“AK-18” ’HAUGHS W “ASHLEY” “RTP” M28 

### 0.46 18.01 21.80

M28 0.78 24 -25 31.40 M28 0.82 17.66 24.80 M28 1.17 17.09 24.05 M28 

### 1.39 16.12 19-90 M28 

### 1.49 11.05 13.55 M28 

### 1.68 7.50 7.05 M28 

### 1.86 9.68 9.65 M28 0-71 28.83 39 -30 M28 

### 1.06 13.80 16.50 M28 

### 1.20 17.36 24.60 M28 1.27 18.89 23.40 CORD 0.71 20 -81 31.60 CORD 0.87 22 “75 32 .OO

M28 0-61 16.00 17.15 M28 0.74 1.18 

### 1.00 M28 

### 1.04 1.62 1.90 M28 

### 1.14 2.02 1.95 M28 1.33 2.23 2.65 M28 1.51 2.46 3.35 M28 1.81 3.16 2.70 M28 1.88 2.38 2.25 M28 0.66 1.28 0.90 M28 

### 1.10 2.37 3-00 M28 

### 1.15 2-91 3.80 M28 

### 1.32 2.79 3.20 CORD 0.79 9.20 

### 10-90 CORD 0.99 12.40 16-70

CORD 0.94 14 -54 20.90 CORD 0.97 14.58 17.60 CORD 1.13 14.18 16 -70

CORD 

### 1.45 26.94 37.40 CORD 

### 1.67 32.70 45.20 CORD 

### 1.64 32.44 39.60

- Country Comfort noncatalyst stove;



### -Sweet Home 

### catalyst, modified stove;

- Haugh’s 

### noncatalyst, low-emitting stove;

-Ashley noncatalyst stove, Crested Butts;



### - Engineering Science test 

### facility in NC; “CRSTO BT*

### -test facility in Crested Butte, CO; “M28” 

### - certification test fuel 

### load,

Douglas fir dimensional lumber;

uCORD” 

### -fuel wood 

### typical of that

used by Crested Butte 

### residents.

I’

- .I.

_ “-.-^-..-.-,---_-I_-- w....1__11 ~_I