Abstract: A filter apparatus that includes a housing having at least one opening by which a fluid is Introduced thereto, a first plate inside the housing and having a plurality of inlets offset from a central axis of the housing and angularly separated from each other. The inlets are configured to pass the fluid thereto. The filter apparatus includes a second plate inside the housing and disposed downstream from the first plate. The second plate has angularly extending outlets disposed at a radial distance from the central axis which is beyond the plurality of inlets such that the fluid is diverted radially outward in passing from the first plate through the second plate. The filter apparatus includes a first filter provided on the second plate underneath the plurality of inlets and configured to trap particles in the fluid which are not diverted to the angularly extending outlets, and includes an exit.

Abstract: Portable air sampling apparatus and methods are provided for passively and/or intermittently sampling air in the breathing zone of a person over extended periods of time. The presence of airborne contaminants can be monitored, as well. Air sampling system performance can be continuously measured and recorded within a data logger. In addition, physical activity levels of a person wearing a portable air sampling system can be continuously monitored and recorded within the data logger. An input device communicates with the data logger and allows a user to store information about his or her personal activities in the data logger. A receiver in communication with the data logger can receive data from remotely located communications devices, such as a Global Positioning System (GPS) signals. A transmitter in communication with the data logger can transmit data from the data logger to remotely located communications devices.

Abstract: Portable air sampling apparatus and methods are provided for passively and/or intermittently sampling air in the breathing zone of a person over extended periods of time. The presence of airborne contaminants can be monitored, as well. Air sampling system performance can be continuously measured and recorded within a data logger. In addition, physical activity levels of a person wearing a portable air sampling system can be continuously monitored and recorded within the data logger. An input device communicates with the data logger and allows a user to store information about his or her personal activities in the data logger. A receiver in communication with the data logger can receive data from remotely located communications devices, such as a Global Positioning System (GPS) signals. A transmitter in communication with the data logger can transmit data from the data logger to remotely located communications devices.

Abstract: Portable air sampling apparatus and methods are provided for passively and/or intermittently sampling air in the breathing zone of a person over extended periods of time. The presence of airborne contaminants can be monitored, as well. Air sampling system performance can be continuously measured and recorded within a data logger. In addition, physical activity levels of a person wearing a portable air sampling system can be continuously monitored and recorded within the data logger. An input device communicates with the data logger and allows a user to store information about his or her personal activities in the data logger. A receiver in communication with the data logger can receive data from remotely located communications devices, such as a Global Positioning System (GPS) signals. A transmitter in communication with the data logger can transmit data from the data logger to remotely located communications devices.

Abstract: Portable air sampling systems and methods are provided for intermittently sampling air in the breathing zone of a person over extended periods of time. Air sampling system performance can be continuously measured and recorded within a data logger. In addition, physical activity levels of a person wearing a portable air sampling system can be continuously monitored and recorded within the data logger. Air sampling system performance monitoring includes measuring pressure drop across a filter and measuring temperature of air flowing through the filter. Physical activity levels of a person can be monitored easily and non-intrusively by measuring changes in electrical capacitance of a transducer maintained in close proximity to the person.

Abstract: Sampling system and method for obtaining representative samples of aerosols in which the particulate concentration is greater than 10.sup.6 particles/cm.sup.3 comprising a sampling probe which operates in cooperation with a dilution system such that a sample of concentrated aerosol can be taken from the gas stream by the probe and almost simultaneously quenched and diluted to a temperature and concentration, respectively, which is acceptable to conventional measuring instruments.

Abstract: A centrifugal filter for separating aerosol particles from a gas stream including a rotatable hollow hub and at least one pair of disks fixedly mounted in spaced apart relationship on the hub within a stationary housing mounted on the hub. The hub is perforated in the region between the two disks and is coupled to a vacuum pump so that the interior of the hub is at a lower pressure relative to the space between the disks. The hub is rotated, causing rotation of the disks. Aerosol particles in a flow gas are introduced between the disks and the housing at the periphery of the rotating disks. The pressure differential produced at the hub perforations draws the aerosol laden gas toward the hub. As the aerosol laden gas enters between the rotating disks and the housing, it experiences an acceleration to nearly the angular velocity of the disks, which results in a centrifugal force being applied to the aerosol particles in a direction opposite to the drag force exerted by the vacuum pump.