Cyclones are designed for in-stack particle sizing applications. The advantages of using cyclones over a cascade impactor is that cyclones have an extremely high particulate collection capacity-up to 10 grams per stage resulting in a bigger sample for accurate gravimetric and chemical analysis, longer sampling times for better averaging and avoids re-loading for each sampling point. Apex recommends cascade impactors for doing particle size research testing.

PM 10/PM2.5  Set combines the in-stack measurement of particulate matter (PM) equal to or less than an aerodynamic diameter of nominally 10 (PM10) and 2.5 (PM2.5 ) microns from stationary sources. The sampling train and operation are identical to Method 201A except that the PM2.5 cyclone is inserted between the PM10 cyclone and the 47mm filter. The PM10 cyclone collects particulate matter greater than PM10 while the PM2.5 collects PM less than PM10 and greater than PM2.5. The in-line filter collects PM less than PM2.5.