Are wood stoves dangerous to health or the environment? Are they being banned? What about PM 2.5 small particles?

No, wood burning stoves are not being banned. Old poorly designed stoves will not be able to be sold after new rules arrive in 2022.

New Ecodesign stoves will replace these and these emit 90% less PM 2.5 particles (via the chimney) than an open fire.

PM 2.5 particles are the smallest particles and are in the air inside and outside of our homes whether we have a stove or not (think the finest of dust particles).

Open fires, the biggest polluters, are not being regulated or banned.

The primary PM 2.5 polluters are vehicles (exhaust fumes, brake dust, tyre wear dust).

Modern Ecodesign stoves are part of a renewable energy system that is carbon neutral.

At the same time as the stove industry was innovating, a few high-profile politicians realised that air pollution in cities was becoming a hot topic and one that needed some swift attention. London, where most of these politicians are based, has high levels of air pollution because so many people are so tightly-packed into a small area and road traffic is dense, slow-moving and constant. So let's focus on London.

During the winter of 2018 and then again in 2019 the British media, prompted by Environment Secretary, Michael Gove and Mayor of London, Sadiq Kahn lashed out:

"Wood burning stoves to be banned", said the headlines, followed by an avalanche of articles about the perceived sins of the wood burning stove (a few years earlier wood stoves were feted as part of the march toward a renewables energy revolution).

Much of what was written in these outbursts turned out to be, at best, sensationalist and, at worst, highly inaccurate. It was also aimed at the wrong target entirely (we shall come to this shortly).

Kudos to the Mayor of London - he did later come out in support of Ecodesign stoves: https://www.london.gov.uk/press-releases/mayoral/tackling-toxic-emissions-from-wood-burners although the good news is not what the press tends to promote so maybe you did not read about this.

So at its worst 10%? Unfairly lumped in with modern wood-burning stoves, old and new, are open fires and it is these that are the biggest offenders when it comes to the PM emissions caused by home heating. In London, 69% of solid fuel installations are inefficient open-fires (40% for the UK as a whole). If anything is to be banned it should be open fires and not wood burning stoves.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/517572/Summary_results_of_the_domestic_wood_use_survey_.pdf

A ten-year-old wood stove has 80% fewer PM emissions than an open fire and the new Ecodesign stoves are even better at 90%. The politicians and media should have focused on open fires which account for 69% of solid fuel fires in London.

That headline that said "Wood Burning Stoves to be Banned" should have stated, "Open Fires to be Banned". But one cannot ban open fires because they are already built into the houses. Nobody is going to storm in and destroy them. So they attacked an easier target - wood burning stoves, the product that is 80-90% cleaner burning and the product that makes up just 31% of the London market. The people who replaced their open fires with wood burning stoves are the one the government and the media should be saluting.

Did you know that in London and many of our cities it is illegal to burn wood on an open fire? The problem is that politicians have not enforced this and the media have never shown an interest. Perhaps it is easier for them to attack something else in order to divert attention from their lack of action?

Oh... those articles about comparing stoves to trucks. Much of that is not correct and I'll be updating that here asap.

PM 2.5 particles are the smallest particles and are in the air inside and outside of our homes whether we have a stove or not (think the finest of dust particles).

A wood burning stove, correctly working, will not exceed small particle safe-guidelines (see foot of this article for Julian's "in the room" analysis) or come anywhere close.

The conclusions of a US survey in 2019 by the Journal of Exposure Science and Environmental Epidemiology were that homes without stoves had a Median PM 2.5 of 6.65  µg/m³whilst homes with stoves were a fraction higher at 7.98  µg/m³(and these were not the latest Ecodesign stoves). This fairly reflects my own tests (although with a chimney liner and Ecodesign stove my PM2.5 increases compared to an unheated home were even smaller) and appears to reflect other studies I have seen.

Just think about that for a minute: a home has a natural and normal amount of 6.65  µg/m³ PM 2.5 particles all of the time, 24 hours a day. Using a wood stove can increase that a smidgen for the few hours the stove is on (whilst still remaining well within recommended safe guidelines). So "very safe" becomes "still very safe". A car tyre with 20% less tread is more dangerous than a car with a brand new tyre but this does not mean the car should be banned or carry a health warning: the car falls within safe levels or it does not.

With regard to clean air DEFRA states that their cleanest and freshest air classed is anything under 11  µg/m³. The World Health Organisation's advice is not to exceed annual average concentrations of PM 2.5 of 10  µg/m³n. Note that this is an average over a whole year so even if your stove was running 24 hours a day, 365 days a year the average PM 2.5 levels would still be within WHO safe guidelines. For most homes, woodburners are only used for a few hours a day, a few months of the year.

My stove, in my house, provides a great deal of warmth and pleasure. I am very happy to state it is very safe and our air is clean.

There are, and always have been, a few, very vocal, killjoys that have it in for "trendy woodburners".

"Get over yourselves".

Recent press reports (late Dec 2020) discussed PM 2.5 pollution inside houses. These articles all stemmed from one syndicated article and this stated:

"The results showed the burners were usually lit for about four hours at a time... During those four hours, average particle levels rose to between 27 and 195 micrograms per cubic metre of air". Under 12 is considered top level clean-air.

This data differs wildly from the US data.

I have a meter in my house that measures particulate matter (PM 2.5's and PM 10's). I can state that these outlandish levels are not comparable to levels in my own house. During the day when the stove is NOT LIT the PM 2.5 figure is always between 4-10 (if not cooking). Lighting the or refuelling the stove makes almost no difference whatsoever and the meter stays within the cleanest top percentile 0-12 "fresh" zone. The chimney pulls well and all particulates leave via the top of the chimney.

Cooking causes the meter to go up and this is to be expected: the cooking particles are not funnelled up a chimney. Toast caused the PM 2.5 level to shoot up to 92 and well-done sausages peaked at 218. So are we going to ban sausages? How about toasters?

One thing is worth mentioning. When the level does rise it takes quite a while (an hour or two) to fall, unless multiple windows are opening to allow through-air (so post-sausage cooking you will be breathing in very high levels of PM 2.5 for an hour or two).

I am starting to wonder if some people just dislike wood burners? Or the "trendy" owners of wood burners?

Article by Julian Patrick, author of The Stovefitter's Manual. Wood burning stove installer (including solid fuel heating systems). Laid down tools in 2013 to write The Stove Fitter's Manual and open a small shop in North Wales (the Wood Stove Hut). Launched Stovefitter's Warehouse soon after due to fast growth of sales. Own stove is a DG Ivar 5.