Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one arrangement, there is an outer, air permeable cylindrical liner, and a first region of fibrous depth media positioned immediately adjacent to the air permeable liner. The first region of fibrous depth media includes non-pleated depth media having an average percent solidity within the construction of no greater than about 3%. The first region of fibrous depth media has an upstream side which is secured to the outer, air permeable liner.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: A filter construction includes a cylindrical pleated filter construction embedded in, and extending between, first and second end caps; and an inner liner positioned downstream from the cylindrical pleated filter. At least two regions of media are positioned upstream from the cylindrical pleated filter construction. The first region of media includes an upstream, region of media including a fibrous media having a percent solidity, within the filter construction, of no greater than about 3%. The second region of media is positioned downstream from the first region of media, and is upstream from the cylindrical pleated filter construction. The second region of media includes a material having, within the filter construction, a different efficiency of filtering than the first region of media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of uniform or constant density depth media is oriented upstream of a region of gradient density depth media. In another, a preferred region of gradient density depth media is constructed, to effect particulate collection in a preferred manner. Preferred constructions described herein, utilize a pleated paper filter oriented downstream of depth media, to advantage.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of depth media is oriented upstream of a second region of depth media. A surface loading media is positioned downstream from the second region of depth media. In an alternate embodiment, a further region of filter media is positioned downstream from the surface loading media.

Abstract: Constructions and methods are described for collecting particulate material from gas streams. In one specifically described arrangement, a region of uniform or constant density depth media is oriented upstream of a region of gradient density depth media. In another, a preferred region of gradient density depth media is constructed, to effect particulate collection in a preferred manner. Preferred constructions described herein, utilize a pleated paper filter oriented downstream of depth media, to advantage.