1. Impact of wood combustion on national pollution

In France, the impact of wood combustion on national pollution varies greatly depending on the emitting sector (domestic, collective, tertiary or industrial) and the pollutant. For example, the main source of fine particulate pollution with an average diameter of less than $2\mathrm{,5}\mathrm{\mu m}$ (PM2.5) is wood heating in the domestic sector (36% of the national emissions mass in 2007), due to a large stock of old, inefficient appliances; conversely, SO ₂ emissions due to wood combustion are almost negligible in the national total (2% of the mass) due to the very low sulfur content of biomass of forest origin....