The combustion of biomass in small scale heating appliances is a source of particulate matter (PM). Studies have shown that increased particle concentrations in the ambient air correlate with adverse health effects in the exposed population. To investigate the emissions of PM from small biomass combustion appliances, such as stoves and boilers, BRITE has set-up a lab facility to measure the performance of such systems. The setup consists of an Electrical Low Pressure Impactor Plus with a two stage dilution system with a porous tube diluter and an ejector diluter, that measures particle concentrations and size distributions in real time with a sample rate of 10 Hz in 14 size classes, ranging from 7 nm to 14 μm. This equipment is mobile and can also be used in-situ on large biomass combustion facilities.