Does anyone know where one finds a description of the EPA test regimen for stove certification? One in "laymans terms" would be preferable over a more technical one. I am just trying to satisfy my curiousity about stove efficiencies and how those numbers are calculated.
The numbers are almost meaningless in the real world. They start by burning what amounts to kindling under carefully controlled conditions of draft. It is stacked to look like so many Lincoln logs in the stove. Try relating that to a real world stove that is stuffed full of larger splits that are fairly tightly packed. The most you can say about the EPA ratings is that they are about the same test conditions for all stoves so at least it is comparing apples to apples.
What reminded me of this was your thread Oldman47 about the ideal steel. When I see efficiency numbers for tube stoves and catalyst stoves, the difference doesn't seem that huge. But the cat stove owners claims make them sound lots more efficient. And then the rocket stove guys jump in, and their claims are even more out there, as much as 1/10 the wood consumption. That seems next to an impossibility, as compared to a "75% efficiency" (or even 50% for that matter) stove, there just isn't that much to gain. So, I just wonder how the testing is done, and how it might or might not reflect on real life results.
Hello I test smoke stacks for a living. I assume you are wanting to know more about particulate testing EPA test method 5H. The basics are you pull a sample of air through a weighed filter. You weigh the filter after and also measure the amount of air pulled through the filter so you can calculate the concentration. So you don't bias the sample there are limits to how fast or slow you pull the sample through the weighed filter. To make it apples to apples you do the testing while burning a known amount of wood/fuel.
Stove is tested hot with crib wood. Wood is milled to size and some of the sides are milled to let air flow between the blocks
Here's some interesting info here about how some stove companies inflate their efficiency numbers Which stove companies can you trust?
Federal Register :: Standards of Performance for New Residential Wood Heaters, New Residential Hydronic Heaters and Forced-Air Furnaces
I found this particularly applicable to this discussion. It is buried under the test methods part of that reference from Huntindog1 . "Commenters overwhelmingly agreed that tuning heaters for crib wood certification tests often results in poorer performance in homes. Based on the existence of a viable draft cord wood test method and the expectation at proposal that the ASTM International (formerly known as American Society of Testing and Materials) test methods for cord wood would be complete soon after the NSPS proposal and that significant testing of wood heaters re-tuned to perform well on cord wood would occur before promulgation of this final rule, the EPA proposed to require testing only with cord wood for compliance with Step 2 emissions limits. We still encourage manufacturers to design wood heaters that best represent in-home performance on cord wood that consumers use as soon as possible. However, the ASTM cord wood test methods have not been completed and only limited testing using the draft methods has occurred."
Once you get to the point no smoke is coming from the chimney I dont think they are gaining a whole bunch. Heck one volcano goes off in the world and negates all the wood stove savings made for the last 30 years. What everyone can do thats much more productive is make sure to use really dry wood and to have smart start ups of your stove to get the heat built up in the stove quicker to get the secondary action going quicker and have a short start up time till you got the stove cruising. Good fire starters and good kindling helps startup and loading loads of good season dry splits and using a top down fire starting technique. Top down works to limit start up smoke as when you load a full load of dry wood in the stove your left with just a very small space in the top of the stove up by the secondary air tubes. Your kindling and fire starter up there in that really small space thats left, well that small space can be heated really hot really quickly getting secondary action going quickly and as soon as that secondary action is going your limiting smoke and emissions from leaving the flue. this trick can be used even when loading on hot coals to speed up the start ups.
Tg = Terra Gram = Trillion Gram Particles and gases in the emissions from the 1980–1981 volcanic eruptions of Mt. St. Helens Authors Peter V. Hobbs, Jason P. Tuell, Dean A. Hegg, Lawrence F. Radke, Mark W. Eltgroth First published: 20 December 1982Full publication history DOI: 10.1029/JC087iC13p11062View/save citation "The total input to the atmosphere of particulate mass from Mt. St. Helens from March 28, 1980, to March 28, 1981, is estimated to be ∼2 Tg" Add too that this info: Q: How many volcanoes erupt each year? A: QUICK ANSWER On average, between 50 and 60 volcanoes erupt each year around the world. This amount averages nearly one volcanic eruption per week.
