Domestic solid fuel combustion, especially in the form of wood burning stoves, has come under the spotlight in terms of adverse air quality due to the particulate emissions. New European Ecodesign regulations will come into force in 2020, preventing the sale of inefficiently burning stoves. However, even the cleanest models currently can produce high levels of particles if used incorrectly. User behaviour, fuel quality and stove operation will affect the quality of combustion achieved, hence real world results can differ considerably from those attained under stove certification conditions. This paper aims to understand the relative magnitude of the factors associated with the highest levels of sub PM2.5 particles and identifies research priorities in order to mitigate these emissions.