Jim Buckley on BAAQMD Staff Report

Buckley Rumford Company
1035 Monroe Street
Port Townsend, WA 98368
360 385 9974
(fax 360 385 1624)
buckley@rumford.com
November 13, 1998
To:
Ad Hoc Committee on Woodsmoke
Carol Bradley, Clerk of the Board
BAAQMD
939 Ellis
San Francisco, CA 94109
415 771 6000 (fax 415 928 8560)

From:
Jim Buckley, Buckley Rumford Co.

Subject:
Fireplace Emissions

Correcting the Record on Rumford Fireplaces:
Having only read the BAAQMD staff report dated 11/2/98 the day before the meeting on November 9th I have not had an opportunity to respond to the report in writing. At this point I just want to correct a couple of errors that relate to Rumford, Rosin and other masonry fireplaces.
On page 3 and again on page 9 the report characterizes masonry fireplaces as "extremely expensive" but in fact masonry fireplaces are only a little more expensive than metal factory built zero-clearance fireplaces. In new construction a "zero-clearance" fireplace with chimney and enclosure might cost about $2,000 while under similar production conditions a masonry fireplace and chimney costs about $2,500. Rumford fireplaces cost about the same as regular masonry fireplaces and have been built under production conditions in California for $2,300. The average Rumford fireplace built in California last year (usually in a high end custom home) cost between $5,000 and $6,000.
The report questions, on page 9, the validity of our OMNI tests. We are not "claiming" anything that hasn't been proven by OMNI - an EPA certified test lab. The two Rumford fireplaces OMNI officially tested were shown to have an average emission factor of 4.76 g/kg and 3.17 g/kg respectively - well within the Washington standard of 7.3 g/kg. The emission rates were correspondingly 18.27 g/hr and 24.71 g/hr which is more than 60% below the 50 g/hr regular fireplaces are said to emit, despite the fact that we were trying to get good emission factor numbers (the Washington standard) - not a rate. Had we been trying to get good g/hr numbers we would have built smaller fires. As it was, the small Rumford consumed an average of 2.1 kg of fuel per hour and the large Rumford 3.1 kg/hr - two and three times the amount of fuel consumed by the average EPA Certified wood stove.
By the way, Dr. Jaasma never tested a Rumford fireplace except unofficially at McNear Labs in 1995. The 1992 study cited in the Report on page 9 refers to a BIA "variation" of a Rumford (which is not the same at all) tested at VPI in what many consider to be a flawed test.
Emission Rate vs Emission Factor:
I would like to chime in with Paul Tiegs, John Crouch and others to advocate use of an emission factor (grams of PM10 per kilograms of fuel) rather than the EPA stove standard expressed as an emission rate (grams of PM10 per hour). Even the staff report calls the stove rate "somewhat unusual in air pollution control" (page 3) and John Crouch calls it the "anomaly". The 7.5 g/hr stove rate is only useful in comparing very similar stoves with each other. It doesn't tell us much about fireplaces or masonry heaters or wood-fired furnaces or even very much about EPA Certified stoves in terms of the emissions we can expect in real life. Flawed and not enforced though it may be, the Washington fireplace emission factor standard expressed in g/kg is better, more realistic, more fair, and less easy to manipulate for evaluating any wood-burning appliance - even stoves. I recommend that the Committee adopt the Washington Fireplace Standard - perhaps with some modification - as a model fireplace emissions standard for the Bay Area.
Margin of Error and Repeatability:
Bill Guy stated that the tests so far are inaccurate and not repeatable within a 35% margin of error. Therefore he is unimpressed with a device like the EcoFire Grate which improves things by only 30% which he views as not significant because it is within the margin of error.
The Buckley Rumford and Frisch Rosin fireplace tests performed at OMNI yielded results which clustered much more closely with about a 10% margin of error and were confirming of many non-official tests we made at McNear Labs in California and Frisch Labs in Washington during 1994 and 1995.
The Meaning of "Significant":
The idea that "significant" improvement has to be 70% to 80% seems ridiculous. The EcoFire Grate is claiming at least 30% improvements and our Rumfords and Rosins are at least 50% better than regular fireplaces. Those are big "significant" improvements early in the game and we expect to do better.

DEVICE EMISSION FACTOR (G/KG) EMISSION RATE (G/HR) LENGTH OF EVENING USE PM EMISSIONS IN A TYPICAL EVENING OF USE
Wood-burning fireplace 12 50 4 200
Rumford fireplace 4 21 4 84
Certified woodstove 7.3 7.5 7 52.5
Certified Pellet heater 2.1 1 7 7
Gas fireplace n/a 0.07 7 0.5
I would submit that the Rumford fireplace is in the ball park. It is "significantly" cleaner than regular fireplaces are assumed to be. It is almost as clean as a certified woodstove over the course of the hypothetical evening, especially if you consider that the Rumford is burning two and a half times more fuel than the stove and putting out more heat. Note that the "emission factor" of the Rumford is 67% cleaner than the regular fireplace and almost 50% cleaner than the certified woodstove.
Thermal Mass:
Thermal mass isn't even mentioned in the staff report except as a criticism of the Washington test method on page 9: "Especially with masonry systems, the result may be a multi-hour period at the end of the test when the masonry is still radiating retained heat, no combustion is occurring, and samples are of clean air." I couldn't have said it better myself. Masonry fireplaces and especially masonry heaters are one burn rate (hot and clean) periodic heaters that rely on their thermal mass to continue heating after the fire has gone out. Isn't it fair to measure the emissions averaged over the whole heating cycle? What can be wrong with an appliance that continues to heat after the fire has gone out and the emissions are zero?
Conclusions and Recommendations:
1) Adopt the Washington Fireplace Standard - perhaps with some modification - as a model fireplace emissions standard for the Bay Area.
2) Permit any appliance or device shown to significantly improve emissions to be installed in existing non-complying fireplaces.
3) Set any objective level of performance you like but avoid out right banning fireplaces by definition which would cut off incentive to develop new fireplace technology, and would seem to be unfair to certain segments of the industry, especially the masonry industry.

DEVICE	EMISSION FACTOR (G/KG)	EMISSION RATE (G/HR)	LENGTH OF EVENING USE	PM EMISSIONS IN A TYPICAL EVENING OF USE
Wood-burning fireplace	12	50	4	200
Rumford fireplace	4	21	4	84
Certified woodstove	7.3	7.5	7	52.5
Certified Pellet heater	2.1	1	7	7
Gas fireplace	n/a	0.07	7	0.5

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