A device for collecting particulate matter suspended in the ambient air through the use of a low pressure air source, comprising: a container extending between an open first end and a closed second end, the container defining a cylindrical outer diameter and a cylindrical inner diameter defining a container interior, a container interior ring extending inwardly from the cylindrical inner diameter and defining an interior ring cylindrical diameter 28, the interior ring cylindrical diameter including an orienting rib; a container output communicating with said container interior located proximate said closed second end of said container; a filter cassette comprising a collection filter adjacent to a filter holder; a retainer having a retainer input removably secured to said open first end of said container for retaining said filter cassette between said retainer input and said container output; a volume reducing plug located within said container interior for reducing the volume thereof; a tunnel extending through said volume reducing plug for providing fluid communication between said container interior and said container output, the tunnel comprising an axial tunnel coupled to a radial tunnel; and an output connector for connecting said container output to the low pressure air source for drawing ambient air into said retainer input for enabling said collection filter to collect particulate matter suspended in the ambient air entering said retainer input, characterized in that a combined weight of said collection filter and said filter holder is less than 600 milligrams and in that the volume reducing plug comprises a top surface and a bottom surface interconnected by a cylindrical wall, an orienting groove being included in the cylindrical wall for orienting the volume reducing plug within said container interior of the container, the orienting rib of the interior ring cylindrical diameter engaging with the orienting groove of the volume reducing plug for aligning the radial tunnel with the container output. a container extending between an open first end and a closed second end, the container defining a cylindrical outer diameter and a cylindrical inner diameter defining a container interior, a container interior ring extending inwardly from the cylindrical inner diameter and defining an interior ring cylindrical diameter 28, the interior ring cylindrical diameter including an orienting rib; a container output communicating with said container interior located proximate said closed second end of said container; a filter cassette comprising a collection filter adjacent to a filter holder; a retainer having a retainer input removably secured to said open first end of said container for retaining said filter cassette between said retainer input and said container output; a volume reducing plug located within said container interior for reducing the volume thereof; a tunnel extending through said volume reducing plug for providing fluid communication between said container interior and said container output, the tunnel comprising an axial tunnel coupled to a radial tunnel; and an output connector for connecting said container output to the low pressure air source for drawing ambient air into said retainer input for enabling said collection filter to collect particulate matter suspended in the ambient air entering said retainer input, characterized in that a combined weight of said collection filter and said filter holder is less than 600 milligrams and in that the volume reducing plug comprises a top surface and a bottom surface interconnected by a cylindrical wall, an orienting groove being included in the cylindrical wall for orienting the volume reducing plug within said container interior of the container, the orienting rib of the interior ring cylindrical diameter engaging with the orienting groove of the volume reducing plug for aligning the radial tunnel with the container output.