Netel | PM 2.5 Dust Sampler We are pleased to provide you with an advanced ambient fine dust sampler, Model FDS 2.5 A measurement of the mass concentration of fine particulate matter having an aerodynamic diameter of less than or equal to a nominal 2.5 micrometers (PM 2.5). The instrument has been specifically designed to meet or exceed the operational requirements of the EPA (Environmental Protection Agency) designated reference method for the determination of fine particulate matter as PM 2.5 in the atmosphere as described in 40 CFR Chapter I Part 50, Appendix L. In principle, an electrically powered sampling pump draws ambient air at a constant volumetric flow rate of 16.67 LPM through a specially designed "Sampling Inlet" which separates particles larger than 10 m (50% cut point) and allows smaller particles to enter an internal particle size separator (Impactor) where the suspended particulate matter in the PM 2.5 size range is collected on a PTFE filter over the specified sampling period of 24 hours. Each filter is weighed (after moisture and temperature conditioning) before and after sample collection to determine the net increase in weight due to the collection of PM 2.5 particulate matters. The total volume of the sampled air is automatically computed by the sampler from the measured sampling flow rate at actual ambient pressure and temperature conditions over the actual run sampling time. The mass concentration of PM 2.5 particles in the ambient air is computed by dividing the total mass of collected particles by the total volume of sampled air and is expressed in micrograms per cubic meter of air (mg/m3).