Forum menu
Nope, the bigger the molecule the better the noise hairs and other normal defences work to trap them, the really small stuff gets into your lungs and does more damage.
https://www.lung.org/our-initiatives/healthy-air/outdoor/air-pollution/particle-pollution.html
Sounds plausible but the last paragraph of the article you quoted says:
The best evidence shows that having less of all types of particles in the air leads to better health and longer lives.
dmorts, Yep I am aware of the concerns regarding outdoor air quality, I was just making a point that I believe they can be run efficiently enough not to poison the user base on my little experiment. In terms of their overall contribution to outdoor air quality (particulate matter) I agree that in heavily built up areas they don’t seem to make much sense. And I am concerned about air quality, I work in a city and have lived in city’s in the past. But, the impact they have, from my limited understanding does appear to depend on quite a number of factors and think user error is a big one and burning in open fires or older stoves. I only get a small amount of white smoke coming out of my flue, even during start up. That’s not to say PM2.5 or PM 10 is not being released but you can’t see or smell the burner (unless you look closely) when you walk past my house even on the calmest of days. Unlike the black smoke you see coming out of some peoples chimneys.
Also, in city’s the low carbon/carbon neutral arguments of burning wood seem to go out of the window, where are people in central London getting their wood from. Mine comes from a tree surgeon less than a mile away or from wind fall in the woods across the road from my house. If I didn’t have this supply I wouldn’t have a log burner. I don’t see a problem with burning locally supplied wood efficiently in more rural areas. There are lots of ifs here. Also, from a carbon point of view, I think you need to look at the wider issues as well, what temperature do you heat your house to, car mileage, air miles etc.
mikewsmith, Yes, I've no idea really as to the accuracy of the monitor in terms of the levels it is recording. The PMs go up when would expect them to, when there's no wind or my wife is cooking. But the log burner doesn't appear to make a difference.
Sounds plausible but the last paragraph of the article you quoted says:
The 2 statements are not exclusive, just that we are better set up to deal with the bigger stuff, the smaller stuff we have no defence for. Coughing up a load of dusty phlegm isn't very nice or good for you as some of it will get through. That and if it's from combustion the associated gasses will make it bad for you too.
Also when you use the word plausible are you waiting to be convinced, it's not a wild theory it's well accepted science.
This is what we used to use in stack
that worked by getting the particles to fall out of a cyclone at the right size distribution and weighing them. Looks like it's still a current method, there were optical solutions but again the temp and humidity had an impact on the particle size distribution. I will say I've been out of that game for a bit now but the principles still hold true,
The 2 statements are not exclusive, just that we are better set up to deal with the bigger stuff, the smaller stuff we have no defence for. Coughing up a load of dusty phlegm isn’t very nice or good for you as some of it will get through. That and if it’s from combustion the associated gasses will make it bad for you too.
Yup, I buy that.
Also when you use the word plausible are you waiting to be convinced, it’s not a wild theory it’s well accepted science.
Well, I think if people are saying that the stuff you can see is not very harmful then yes, I'd need some convincing. Victorian chimney sweeps got cancer on their skin simply from rubbing themselves on carbon all day. So the visible stuff is pretty nasty, even though a portion is not getting right into your lungs.
...but in general no, I'm not waiting to be convinced that your body filters out a load of the bigger stuff before it gets to your lungs. "Plausible" is just something you say when you think something is true but you haven't seen the evidence yet.
We had a wood burner put into our inner-city house last year - DEFRA approved, so the air control always allows a fair amount of air flow, even when "closed". We use very well seasoned, dry wood, delivered by a local supplier. Bloody hell does it go through that expensive wood quickly! It's exhausting constantly having to get up from the sofa to feed it.
Lush mind. If it gets banned I suppose we can put some lightbulbs in it and turn the gas heating on.
That looks quite high tech compared to the little hand held thingy I've been using. I believe it is a laser particle detector.
“Plausible” is just something you say when you think something is true but you haven’t seen the evidence yet.
I think the HSE will have some good reading on it, plenty to google and have a read through. USEPA also has some great stuff and pushed through a heap of the measurement standards.
rickonwheels, I think that is the correct attitude to have. If for whatever reason I didn't have a well-seasoned supply of wood I’d just have to use the gas for 100% of the heating and leave the log burner as being a “feature” of the living room. It’s no big deal. A lot of people don’t have this option. On the cost of wood I don’t pay much because I get it green from the tree surgeon or free when a tree blocks the Road. It’s does take quite a lot of space to store and season but I quite enjoy chopping and stacking it.
How did you get to 4%?
They explained it in detail in the show. 4% is the lowest estimate relative to *all* airbourne particles in winter as opposed to just invisible particles emitted by human activity from the Uk
Ok, we are on the same page and hearing the same thing. The 4% was the lowest PM2.5 from burning wood that they'd measured in the countryside. It's the lowest of the range of 4-6% mentioned by Dr Fuller. However nowhere do they say that
pollution from would burners could be as high as 38% ..... could be as low as 4%
Two different things have been conflated there. In the show they state the 38% and the 4% are of different denominators, i.e. percentages of different things
The 38% is an estimate of the emissions the UK makes into the air in the UK. The 4% is the lowest of the measured* countryside range of all particles in the air in the UK, only 50% of which are emitted** by the UK.
*Granted there will be some estimation/guesswork in this. E.g. they'll have to work out what's different about a burnt wood particle burnt in the home and one that's not burnt in the home.
**Of which the Government has estimated 38% come from burning wood
Two different things have been conflated there. In the show they state the 38% and the 4% are of different denominators.
Yup, two numbers measuring different things. The government could have used either number. dangeourbrain was saying that the 4pc would be the wrong number to use and it would be better to pick a different statistic to make the point. I think he's right. At no point did he say the two numbers were measuring the same thing, and the show explicitly states why they aren't comparable.
and it would be better to pick a different statistic
I meant "and the Govt got it right it *was* better to pick a different statistic". "Would be" implies something a bit different. 🙂
Cheers OOB, that's pretty much exactly my point, i would however have shied away from saying, quite so explicitly the government did, said, thought or even was capable of conceiving the existence of something right for fear of the inevitable backlash of agreeing with the Tories on here, even by accident. I expect you'll be getting your shoes well and truly peed in now.
Cheers OOB, that’s pretty much exactly my point, i would however have shied away from saying, quite so explicitly the government did, said, thought or even was capable of conceiving the existence of something right for fear of the inevitable backlash of agreeing with the Tories on here, even by accident. I expect you’ll be getting your shoes well and truly peed in now.
When I said government I meant the Civil Service, of course, not the Ministers. 😀
https://uk-air.defra.gov.uk/assets/documents/reports/cat05/1801301017_KCL_WoodBurningReport_2017_FINAL.pdf
https://www.bmj.com/content/350/bmj.h2757/rr-1
https://consult.defra.gov.uk/airquality/domestic-burning-of-wood-and-coal/supporting_documents/180129%20Evidence%20background%20documentation.pdf
Too much of a good thing there, can't read it all. I *did* read the Summary of the last one which was pretty good and seems to directly state many of the numbers featured in the More Or Less show. Also gives a value for Cardiff which I guess counts as non-rural.
dangeourbrain was saying that the 4pc would be the wrong number to use and it would be better to pick a different statistic to make the point
I understand now. I thought that I'd somehow missed something in the show about the potential errors in the estimation of the 38% and that the estimation could actually be as low as 4%.... the premise of the show is about finding flaws in numerical methods after all!
Always go with conservative (little c) it's the basis of all environmental impact analysis. Because if worst case is ok or can be mitigated to be ok then you can't really go wrong.
So we all agree burning wet wood in cities is bad. Even DEFRA agree.
But then even they don't have much of an issue with dry wood burnt in an appropriate appliance in a rural area....
Not to say I think this issue is unimportant or the analysis wrong. But I do find it deeply concerning that as a country we seem to be working so hard to focus our environmental policies and headlines on issues away from the relatively massive problem our planet faces of greenhouse gas emissions and fossil fuel burning. So many easy opportunities missed (zero carbon homes rule scrapped, a weak target on cars) or deliberately avoided (this government actively worked to kill onshore wind) in that area. Our priorities look so very wrong to me.
So we all agree burning wet wood in cities is bad. Even DEFRA agree.
But then even they don’t have much of an issue with dry wood burnt in an appropriate appliance in a rural area….
I think there should be a tiered system, depending on what's available at your house, with subsidies for installing the cleanest possible option. If you can get gas from the grid, why do you need to have a wood burner? If you don't have central heating you could get help with install costs. If you're off grid then other options can be looked at, including a wood burner.
@luket UK Governments are pretty bad at implementing such policy changes. It always pulls the punch, generally stripping the guts out of any proposed policy and leaving the only headline, with a few meagre and impotent changes.
Nope, the bigger the molecule the better the noise hairs and other normal defences work to trap them, the really small stuff gets into your lungs and does more damage.
The motor manufacturers need to know this, diesel engine particle filters do nothing to stop the fine stuff.
It would also be nice if th esame worst case method were applied to diesel cars i.e. test them being ragged from cold over the first 5km - which is how most kms are really covered.