Abstract: A photometer device including an inlet passage for receiving a fluid such as an aerosol at a specified flow rate, an outlet passage separated from the inlet passage by a gap, and a radiation passage across the gap. The flow rate and the significant dimension of the inlet passage are set to produce a laminar flow of the aerosol. The gap and the significant dimension of the outlet passage are set to maintain a laminar flow of the aerosol across the gap to prevent contamination of the radiation passage.

Abstract: An ambient particulate sampler assembly including an upper section with a nozzle entry and an impactor nozzle housing removably receiving a single nozzle jet. A lower section is removable from the upper section and includes an impaction chamber with one or more outlets. A set of different size nozzle jets are provided and each is insertable in the impactor nozzle housing to allow the user or manufacturer to selectively choose a particular measuring criteria.

Abstract: A photometer device including an inlet passage for receiving a fluid such as an aerosol at a specified flow rate, an outlet passage separated from the inlet passage by a gap, and a radiation passage across the gap. The flow rate and the significant dimension of the inlet passage are set to produce a laminar flow of the aerosol. The gap and the significant dimension of the outlet passage are set to maintain a laminar flow of the aerosol across the gap to prevent contamination of the radiation passage.

Abstract: A gas sampling apparatus including a flexible, substantially gas-impervious, closed bag and a valve assembly mounted in a wall of the bag for providing control of gas flow between the interior and exterior of the bag. The valve assembly includes a valve body mounted in the bag wall for providing a first gas conduit to and from said interior of the bag, and a valve stem for providing a second gas conduit, the stem terminating at one end in a ball mounted on the valve body. The stem is movable about the ball between an opened position in which the gas conduits are in communication with one another and the bag may be filled or emptied through the coupled conduits, and a closed position in which the ball seals the first conduit. A valve cap is provided for capturing the stem at variable pressures between the valve body and the cap. The cap has a slot in one side in which the stem is movable tranversely to its long axis between its opened and closed positions.

Abstract: The calibrator device is used for calibrating the flow indicator (rotometer) of an air pollution sampling instrument known as a high volume air sampler which determines the concentration of the total suspended particulate in the ambient atmosphere. The calibrator is of cylindrical shape having an annular passage and centrally disposed knob at one end and a pair of aperture plates at the other end, one of which is fixed in position and the other one of which is rotatable by means of the knob. Each calibrator defines a flow characteristic represented by a graph of flow versus orifice pressure, and by setting the flow resistance at different sequential values by rotation of the knob a plot is established of true air flow in cubic feet per minute (cfm) versus observed flow meter reading.