Our Defra Approved Stoves. Officially classified as DEFRA exempt stoves, these models are suitable for use in houses that fall within Smoke Control Areas. To be classed as DEFRA exempt, stove manufacturers must be able to demonstrate to DEFRA that the stove can burn wood cleanly without producing smoke. DEFRA stoves typically feature air vents which cannot be fully closed, ensuring the stove retains a constant supply of oxygen. This makes the combustion process cleaner and more efficient, minimising soot production. DEFRA approved multi fuel stoves can also be used to burn approved smokeless fuels such as anthracite, giving you greater flexibility in your fuel choices. Check with your local council before buying to see if your home is within a Smoke Control Area.