Patent ID: 8671738

Claim:
A cascade impactor comprising: a series of concentrically-arranged collection stages and a terminating filter or filter adapter stage, each of said collection stages comprising an elongated structure with a cylindrical shape, each of said elongated structures having a top end and a bottom end, the wall of each of said elongated structures having an inner surface and an outer surface and further characterized by a single inner diameter, a first outer diameter, and a second outer diameter, the top end of each of said elongated structures being open and the bottom end of each of said elongated structures being closed with a flat surface, each of said elongated structures further comprising a region wherein the second outer diameter is less than the first outer diameter to form an orifice-containing region on each of said elongated structures, the wall of each of said elongated structures further comprising at least one orifice positioned in each of said orifice-containing regions and perpendicular to each of said walls and through which aerosol-containing air flows, wherein, for each of said elongated structures, the first outer diameter is sized to fit within and slidably seal within the inner diameter of the elongated structure of the next stage in the series, and wherein particles entrained in sampled air are collected on the inner surface of the wall of the stage opposite said respective at least one orifice.