Three sources accounted for 91% of Canada's national black carbon emissions (45 kt) in 2013. Off-road vehicles emitted the largest proportion, representing 35% (16 kt) of national emissions, followed by transportation (road, rail, air and marine) representing 30% (14 kt) and home firewood burning, representing 26% (12 kt). The remaining 9% of emissions came from the oil and gas industry and other industries