Abstract: A pocket filter adapted for filtering grease and other liquid aerosols has first and second depth loading media with a separator that prevents wicking thereby to extend filter life and capacity. The first layer is also of lower efficiency than the second to distribute loading and further extend life. The spacer may be of unwoven fiber mesh. Various feature of the pocket filter ensure free flow of effluent streams.

Abstract: A pocket filter adapted for filtering grease and other liquid aerosols has first and second depth loading media with a separator that prevents wicking thereby to extend filter life and capacity. The first layer is also of lower efficiency than the second to distribute loading and further extend life. The spacer may be of unwoven fiber mesh. Various feature of the pocket filter ensure free flow of effluent streams.

Abstract: A planar omni-directional inlet assembly is provided for installing on a device, such as a dry filter unit, that draws a fluid medium, such as ambient air, to collect particulate matter suspended in the fluid medium onto a filter. The inlet assembly includes an annular platform removably positionable on the device; an annular nozzle to direct the air from the platform; an annular impactor disposed downstream of the nozzle; a housing that disposes the filter downstream of the impactor; and an exit for passing the air from the filter to the device. The impactor presents a flow obstacle for a portion of the particulate matter. The housing directs the air through the filter. The housing includes a base with a first cavity and a lid with a second cavity such that the filter is disposable between the first and second cavities.

Abstract: A diesel particle virtual impactor sampler provides for a total flow through a virtual impactor after the flow passes through a classifier that removes particles substantially larger than the cutoff point of the virtual impactor. The virtual impactor has two outlets, one for minor flow and one for major flow. In a preferred embodiment, filters are used for separately filtering the major and minor flows and collecting the particles carried thereby so that a determination of the concentration of particles above and below the cutoff point can be obtained. Alternately, the major and minor flows and the particles can be passed through particle analyzer instruments for a direct particle measurement of each of the flows.