Saturday 20 July 2019

The burning question: Is your wood-burning stove harmful?

The UK government has just announced a crackdown on woodburners that give off large amounts of hazardous emissions. Regina Lavelle looks at what you can do to reduce the health and environmental impact of your fire

Old stoves can be detrimental to your health — invest in an eco stove to reduce emissions by up to 80pc. Photo: Getty Images/Cultura RF
Old stoves can be detrimental to your health — invest in an eco stove to reduce emissions by up to 80pc. Photo: Getty Images/Cultura RF
Old stoves can be detrimental to your health — invest in an eco stove to reduce emissions by up to 80pc. Photo: Getty Images/Cultura RF

Regina Lavelle

Sleek and well-designed, cosy without being naff, the wood-burning stove has been the accessory of choice for any self-respecting middle-class home for some years now. It also burnishes our eco-credentials alongside our banishment of single-use plastics and recycling obsession.

Or so we thought.

Yesterday the UK government announced (that sentence never ends well for us, does it?) a crackdown on fossil fuels to address the country's air quality crisis. In the UK government's sights, as part of its Clean Air Strategy, are proposals to ban the sale of polluting fuels and ensure only the cleanest stoves are sold by 2022.

Considering stoves are not cheap - they range in price from roughly €200 to well over €2,000 - such proposals are inevitably causing much consternation.

For those who would never dream of burning coal, drive a Hybrid and whose only environmental extravagance is a guilt-laden, once-a-month 60C whites wash, news of their eco-misdemeanour has not been well received. But rather than being merely a UK matter, the proposals are actually an EU initiative, according to Dennis Milligan, Head of Communications at the Stove Industry Alliance - a UK body which represents the industry with DEFRA, Michael Gove's department.

"What DEFRA is implementing is eco-design from 2022. It's European legislation and it's intended to reduce emissions from combustion appliances all across the board. Eco design covers the main emissions from a stove, from particulate matter (PM) and some carbon gasses, but the main one would be PM," Milligan says.

While no new measures have been announced here yet, yesterday a spokesperson for the Department of Communications, Climate Action and Environment said that a new National Clean Air Strategy was expected to be launched in coming months.

So what exactly is the problem with stoves? The issue at stake is fine PM, a "very, very fine dust", explains Patrick Kenny, Air Quality Manager with the Environmental Protection Agency, EPA.

"PM2.5 - the PM referred to is micron so it's particulates smaller than 2.5 microns - is the pollutant arising from domestic solid fuel burning.

"In Ireland, that's the predominant source of an estimated 1,100 premature deaths, according to the European Environment Agency's 2018 Air Quality Report."

The United Kingdom's comparable figure for this particulate is 31,100 premature deaths.

Particulates are caused by incomplete combustion.

"Burning something solid but not burning it completely generates particulates.

"Unless you're burning a solid fuel to a high temperature, you won't have complete combustion, the lower the burn temperature, the higher the particulate produced," says Kenny.

"You have a much lower burn temperature from an open fire compared to any stove. And then you have a percentage of that smoke carrying particulates and other pollutants coming back into the room."

The particulates are dangerous as they're too small to be trapped by the body, and so travel into the lungs and cardiovascular system where they can cause disease or exacerbate existing conditions, including asthma.

Particulates can be comprised of both organic and inorganic matter. Not all are chemical, although some can be.

And while most of us might associate most lung diseases, including Chronic Obstructive Pulmonary Disease (COPD) with smoking, poor air quality - including that induced by burning fossil fuels - can play a role.

"Some of the guidelines we use for lung disease people usually associate with smoking. But our most recent guidelines in 2018 are clear on the role of burning biomass fuels, including wood-burning, and its contribution to the development of the disease process," says Dr John Garvey, Consultant Respiratory Physician at St Vincent's Hospital.

"Wood smoke can lead to outdoor pollution - it pumps smoke and toxins into the outdoor area.

"It can affect people living with lung issues, children with asthma and older adults with lung disease, and some of our associations are starting to act on this now.

"Fine particulate pollution is a consequence of fossil fuel burning, including wood burning. And the particulates get into the organs in the body, get into the lungs, the cardiovascular system."

Although, unlike the UK, Ireland has not exceeded the air quality limits set by Europe, Kenny of the EPA admits that we have exceeded the "tighter guideline values set by the WHO, which are not legally in place".

But Dr Garvey highlights the greater incidence of respiratory issues, especially asthma, amongst the Irish population.

"Ireland has the fourth highest prevalence of asthma in the world, and it is not a benign illness. One person a week dies from asthma and that figure may be higher. There is an under-appreciation of the importance of asthma and the risk of death in this country."

So what can we do? And if you have invested in a wood-burning stove, how do you reduce the risk of it being a pollutant?

The good news is that stoves are immeasurably better for your family and the environment than open fires and even if you don't want to change your stove, there are ways to mitigate its impact.

According to Milligan, the current UK proposals do not oblige those with older stoves to change them. The proposals will only come into force in 2022.

The new generation of stoves - those cleaner models referred to by Michael Gove - are the so-called 'Eco stoves'.

They offer a more complete combustion, thereby reducing emissions.

Milligan explains: "All stoves will control the burn better than open fires, but it's a matter of degree. Stoves control the burn, new stoves control the burn better.

"We conducted some research into the difference between the models. The results were that an eco-designed stove produced 90pc fewer emissions than an open fire and 80pc fewer than a stove produced 10 years ago.

The reduction in emissions have been progressive. In February 2017, the Stove Industry Alliance launched its eco-design ready range. Now it has 400 models from most of the manufacturers in the UK, and these manufacturers will distribute in Ireland.

For those concerned about replacing an existing model, Milligan says that no additional change is required to the chimney.

"All the changes in technology are in the firebox. One of the ways they do that is they introduce combustion higher up in the fire chamber so the smoke is re-ignited so there is less of an incomplete combustion."

Although the new models will retail at the same price range as the current models, Milligan believes that the cheaper models will drop out of the market and expects the price range to be upwards of £800 (€900).

"Some of the cheaper stoves will drop off the market," he says.

If the thought of changing your new wood-burning stove - and the additional cost - brings you out in a cold sweat, there is an easier way to reduce your emissions without spending any money - stop burning wet wood.

"Freshly cut wood can contain 60-85pc moisture, depending on the variety, which means you're burning water and therefore creating a lot more smoke. All the research points to wet wood contributing to emissions, so only use dry wood and that will help."

Irish Independent

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