… and emphasis on the ‘no bias’ here. This blog post doesn’t exist to sway you from one side of the debate to the other but to help separate the noise from the facts. Here at Ideally, we fundamentally believe that when people are presented with facts, they will make sustainable and ethical choices.
So let’s explore the facts together.

Wait, what have I missed? Ok, let’s bring you up to speed. A recent article from ‘The Guardian’ titled “Wood burners triple harmful indoor air pollution”, about a study made by scientists at the University of Sheffield, has certainly rattled some cages.
The article states that wood burners triple the level of harmful pollution particles inside homes and should be sold with a health warning and, according to scientists, should not be used around elderly people or children. It is claimed that tiny pollution particles flood into the room when the burner doors are opened for refuelling.

Is this true? To an extent, yes. However it should be noted that a study of indoor pollutants within 19 homes that are using older wood burners with older emission standards is, in our opinion, not a very comprehensive study at all. 
The reality is that the “solid fuel industry” is an unregulated mess and has been for a long, long time. It has been (and continues to be) plagued by reactionary thinking, procrastination and all round regulatory blindspots. 

So, what does this have to do with indoor pollutants? Unregulated industry is bad for many reasons. It results in cheap quality and polluting products flooding the market, many badly installed appliances, irregular servicing and a lack of consumer awareness on the good and bad practices when operating solid fuel appliances. 
These all contribute to pollution which subsequently results in indoor pollution.

Let me explain:

  1. Not all solid fuel appliances are equal. 

Let’s start right at the bottom with open fires. Open fires inside the home are polluting, outside and in. There really isn’t a way of sugar coating the facts here and frankly, legislation is needed to restrict the use of these big polluters.
Then in the middle of the spectrum we have old or low quality stoves which are typically more efficient than open fires but can still unfortunately emit large quantities of pollutant particles.
Finally we have Eco-design stoves. These are stoves that have been made to comply with the most stringent emission standards that will at last become law for all new appliances installed from 2022. These are the most efficient, low emitting stoves on the market and are in most cases up to 95% more efficient than open fires. Additionally Eco-design stoves have been endorsed by the ‘Mayor of London’ and ‘DEFRA’ as a way of curbing emissions.

So, what makes a stove Eco-design? Eco-design stoves are essentially gentrified incinerators. They look and feel great but most importantly, they are considered clean burning. This means that they have the means of not only combusting solid fuel but also most of the gases that are emitted during this process.

They can burn the gases too? Yes. Eco-design stoves actually recycle the gases emitted from the fuel in order to achieve higher, cleaner heat. This is how log burning in an Eco-Design stove works:

  • Initially the remaining moisture in the log vapourizes, little heat is produced.
  • At 250°C the log begins to break down chemically releasing volatile gasses. 
  • When the temperature reaches 600°C and above the gasses will begin to burn, generating even more heat from the process.

This is something that you will never achieve in an open fire.

No matter how inconvenient, we need to recognise the facts. We need to restrict the use of open fires and cheap quality stoves for everybody’s benefit.

  1. Absent regulations has resulted in poorly maintained and serviced appliances.

Chimney sweeping is an absolute vital service to reduce the spread of indoor pollutants and maintain the safety and performance of all solid fuel appliances. Chimney sweeping eliminates the build up of soot that comes from burning solid fuel and helps to maintain an adequate draught, minimizing the risk from indoor pollutants. This should be done at least once per year. 
Sadly, this service is often overlooked and it is not uncommon for some consumers to go a good few years between chimney sweeps. In some cases it is overlooked completely. This ultimately leads to higher indoor and outdoor pollutants, higher risk from deadly fumes such as Carbon Monoxide and higher chances of having a chimney fire.

Let’s look to our friendly rivals over in Germany where it is legal for a chimney sweep to access your property via the roof and sweep your chimney if there is a cause for concern over the safety of the appliance indoors. 
I suppose that is one way of dealing with the problem, albeit messy! The fact of the matter is that their system works in keeping solid fuel appliances safe and well maintained. 

Why don’t we take the best parts of the German system and create a system that works for us in the UK? This is exactly what we should do and most chimney sweeps will agree with this. We need to create a system where annual chimney sweeping and appliance servicing is compulsory. We need to support our chimney sweeps by giving them the powers to, perhaps not force a sweep as they do in Germany, but to decommission dangerous appliances and report bad practices without fearing that they will lose a valuable customer (as is often the case today). 

Let’s support our chimney sweeps with actual powers to help us maintain a safer, cleaner environment.  

  1. Absent regulations has resulted in overall low consumer awareness on how to operate solid fuel appliances properly.

This then contributes to overall lack of awareness on the good and bad practices when operating solid fuel appliances. Incorrect use of solid fuel appliances, such as open fires and wood burners, can lead to all sorts of potentially fatal problems like Carbon Monoxide leakages.

What is considered good or bad practices when operating a wood burner? 

With the blog topic of indoor pollutants in mind, these are some of the practices that you should be aware of:

  • Only burn seasoned or kiln dried logs: these are logs that have a moisture content that is between 5% and 20%.
  • Arrange for your chimney to be swept at least once a year by a trained professional.
  • Do not burn wet/damp logs or painted/treated timber: this can block or corrode the flue leading to higher risks from indoor pollutants, CO leaks and chimney fires.
  • Make sure that your stove is the correct kW size for the room: some scenarios may require a vent in the wall to ensure an adequate supply of free air to the appliance. Remember to never block a vent in your home.
  • Only reload your stove when the flames have died back and there are glowing embers inside the chamber or use a stove thermometer to help you identify when is best to reload the stove. This reduces the risk from indoor pollutants and boosts efficiency by up to 30%.
  • Do not stack logs down the sides of your stove: this raises the risk from spontaneous combustion and indoor pollutants.
  • Never leave the doors open during operation: this raises the risk from indoor pollutants.
  • Burn smokeless fuel instead of house coal: there is significant risk from pollution when burning house coal due to the large amounts of sulphur that is produced. House coal as a home fuel is due to be phased out between 2022 and 2023.

Don’t forget that it is generally considered good practice to simply open your windows once a day for about an hour to help reduce the amount of indoor pollutants in your home.

It is critical that we clamp down on dodgy installations and begin boosting consumer awareness on how to maintain safe and efficient appliances.

What exactly are indoor pollutants and where else do they come from? Sadly, our home is full of tiny indoor pollutants that we cannot see but can be very bad for our health in large quantities. Indoor pollutants in our home come from many of our everyday uses and can be broken down into 4 categories:

  1. Particulate matter comes from everyday uses such as toasters, gas hobs and candles. This is the pollutant mostly associated with improper use of wood burners, namely PM.25. PM.25 is also the main culprit emitted by diesel engines that is often brought into your home, for example, via your clothes.
  1. Gases including Carbon Dioxide (CO2), Nitrogen Dioxide (NO2) and Carbon Monoxide (CO). Inadequate ventilation within your home can cause high levels of CO2 and NO2 from gas appliances, which can both make you very sick. CO is associated with many combustion appliances including boilers, gas fires and wood burners. Regular servicing of these appliances is vital to ensure your home is safe from this deadly gas.
  1. Volatile organic compounds (VOC) are chemicals found in a wide variety of materials. VOCs evaporate into the air at room temperature, forming vapours that we breathe and have different risk levels. High risk VOCs include benzene from petrol, cigarette smoke, paints and solvents. Medium to low risk VOCs include Terpenes and Formaldehyde which come from scented toiletries, bathroom cleaners, new flat pack furniture, lino, carpets, glues and home insulation.
  1. Microplastics are probably the scariest of them all because they are so widespread, unavoidable and still a relatively new discovery. Research shows that many of the microplastics in our bodies come from the air we breathe. Due to their small size, microplastics can be inhaled and may induce a wide range of diseases including respiratory and cardiovascular diseases, as well as cancer.
    More than 300 million tons of plastic are produced each year of which half of that gets dumped in less than a year. Out of the plastics produced, only 9% is recycled; the remaining 91% enters the air, land and water as waste. Parts end up in our lungs and they stay in the lung tissue or enter the bloodstream, as the body is not able to rid itself of the tiny plastic particles. Babies and toddlers who crawl on the floor are the most vulnerable, and children more generally are most at risk as their respiratory systems are still under development.
    Microplastics in our homes come from plastic fibres released from synthetic clothing and textiles used in home furnishings and carpets. They are also released from other household products such as kettles, microwaves, dishwashers and baby bottle warmers.

Our conclusion is: though we believe that the recent report linking wood burners and indoor pollutants was inequitable, improper and inconclusive, science should never be ignored. 

However, you’ll be forgiven for ignoring the media hype. Wood burners are not the next asbestos, but the warnings around them should be taken seriously. Indoor pollutants are harmful to our health and we should do everything we can to reduce them within our homes. 

What this study does reveal is the cracks running within the solid fuel industry which is risking its own extinction by not fully addressing the problems at hand.
We cannot tackle air pollution with half arsed measures like only restricting all new stove installations to Eco-design stoves. We need to restrict the use of open fires and upgrade all the older polluting wood burners to Eco-design standards.

The industry needs to adapt and evolve faster to prove that it can function without polluting peoples homes whilst supporting the thousands of jobs within it, or it faces a blanket ban on everything, no matter how good an Eco-design stove really is.

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