Patent ID: 7759123

Claim:
Apparatus for separating and collecting particulates entrained in a flow of fluid, the apparatus comprising: (a) a virtual impactor capable of separating a fluid stream into a major flow and a minor flow, the major flow including a minor portion of particulates that are above a predetermined size and the minor flow including a major portion of the particulates that are above the predetermined size, the virtual impactor including a minor flow outlet through which the minor flow exits the virtual impactor; (b) a collection surface upon which particulates entrained within the minor flow can impact; (c) a prime mover drivingly coupled to one of the virtual impactor and the collection surface, enabling a relative position of the virtual impactor and the collection surface to be selectively manipulated, such that at least one orientation enabled by the prime mover results in the minor flow of fluid that is moving through the minor flow outlet being directed towards the collection surface; (d) means for enabling collection of a sample from the collection surface; and (e) a trigger controllably connected to the means for enabling collection of the sample, the trigger being responsive to a condition other than time that is indicative of particulates of interest having been accumulated on the collection surface, such that when the trigger determines that the particulates of interest have been accumulated, said trigger activates said means for enabling collection of the sample, wherein the trigger comprises at least one of: (i) an optical detector configured to activate a sample collection when a concentration of particulates in the minor flow reaches a predefined threshold; and (ii) a sensor configured to detect an environmental condition indicative of particulates of interest being accumulated on the collection surface.