[Stoves] News 24 Jan 2017: Dirty woodstoves cause a health crisis in London

[Andrew Heggie]

On Tue, 31 Jan 2017 14:30:53 +0000,Crispin Pemberton-Pigott
<crispinpigott at outlook.com> wrote:

>Does the average home still have a solid fuel burning device? My aunt's house has one on each floor.

This could get a bit off topic but I'll try to answer; the housing
stock is old so most houses built before about 1970 would have had
chimneys for open fireplaces ( these being the main reason for poor
combustion), yes there would have been fireplaces in most rooms, my
little cottage had two upstairs and two down, the upstairs ones have
never been used in the 40 odd years we have been here, a pellet stove
is connected to one room downstairs and a 30 year old Jotul wood stove
to the other. I don't cook on the latter but may try some  maize
tortillas on it soon.

As with most houses in urban areas we have natural gas central heating
(wet or hydronic to you) also for domestic hot water but we only use
two downstairs radiators,  with wood providing much of the space
heating.
>
>>Raw coal was banned in "smokeless" zones. Modified solid fuel "smokeless coal" replaced it within these zones.
>
>As you will be aware, the thinking is that there are no smokeless stoves, only smokeless fuels. Interesting, eh?

Well it was a pragmatic decision, people were not likely to invest in
clean burning devices and were likely to continue using open fires, so
refining the fuel made sense.
>
>>In fact "DEFRA" approved wood stoves burning wood fuel within the range of moisture contents specified by the manufacturer are exempt for use in smoke control areas and have been for some time.
>
>I am not familiar with the DEFRA rating. I will endeavour to find out more.

http://www.stovax.com/stove-fire/stockton-wood-multi-fuel-stoves/stockton-4/

links to a cheap one my daughter uses, as long as the wood is below
25% moisture content  wet weight basis there is no visible smoke after
20 minutes as long as a flame is maintained. In this climate it is
really necessary to keep the wood under cover from September or it
picks up moisture from rain. It needs to be open to the air from May
to September to lose moisture from ~50% .

Her house also has gas central heating, is more modern and well
insulated, with double glazing. Ours was built in 1862, has solid
walls, a combed roof (so does not lend itself to insulating) and
single pane glass windows.

We are not in a smoke control area and wood was freely available from my work.

Now to get on topic; I am far more interested in what people on the
list know about the spectrum of sizes of particulates from cook
stoves. There is an argument going on here between petrol heads and
medical practitioners about soot emissions from wood smoke and diesel
engines and some of the diesel enthusiasts are claiming that in the
damaging smaller sizes (which seem to be PM2.5 rather than PM10,
petrol engines are as bad??

So what sizes of particles are we seeing when testing  stoves?

Andrew