The United States of America As Represented by the Secretary of

The United States of America, As Represented by the Secretary, Department of Health and Human Services

Airviz Inc.

Charles D Litton

Martin Hertzberg

Michael Allen Taylor

Illah R Nourbakhsh

William H Schiffbauer

Jon C Volkwein

Dömötör Gulyás

Kenneth L Cashdollar

Randall Garloff

An optical-particle sensor head comprises an electromagnetic radiation source to transmit electromagnetic radiation toward the detection chamber; one or more baffles, between the light source and the detection chamber, to restrain a spread of the electromagnetic radiation from the electromagnetic radiation source; and at least two off-angle photo-sensors.

Optical-particle sensor head

Apparatus and methods are disclosed for analyzing particles, such as coarse particulates, fine particulates (e.g., diesel particulate matter), and combustion aerosols, using light-scattering sensors and/or ionization-type sensors. In one disclosed embodiment, a particle monitor includes an ionization module and a controller adapted to receive an output signal from the ionization module. The controller is operable to translate the output signal into the mass concentration of particulate matter within the ionization chamber. In another embodiment, a particle monitor includes a light-scattering sensor and an ionization sensor. The monitor is configured to measure separate mass concentrations of sub-micrometer particles and larger dust particles in an atmosphere having both types of particles.

Apparatus and methods for analyzing particles using light-scattering sensors and ionization sensors

An infrared radiation measuring pyrometer whose output is used to calculate both particle and gas temperatures from an explosion or fire. Preferably four infrared wavelength measurements are made to compute the particle temperature and two infrared wavelength measurements to compute the gas temperature. Especially constructed to operate in an explosion environment, the invention allows the simultaneous and continuous measurements for both particle and gas temperatures. Planck's Law is used to relate the radiation emitted from the particles and/or gas to the wavelengths observed, the emissivity of the object at that wavelength, and the temperature of the particles and/or gas. For each specific wavelength detected at the pyrometer there is an output voltage which can be related to the flame radiation. The actual temperatures for the particles and/or gas are determined by plotting the relative radiation-sensitivity factor times measured voltage at a specific wavelength - versus wavelength and then comparing these plots with Planck black body radiation curves or by using a computer or calculator program.

Multichannel infrared pyrometer

An instrument to detect submicron particles by charge-transfer attachment. The instrument is made up of a charging chamber with two concentric cylindrical electrodes, a remote third collector electrode, and a pump to force ambient air through the charging chamber and into the collection electrode. The innermost electrode of the charging chamber is supplied with a radioactive material having a gold foil covering. This material can create a small bipolar region symmetrical to the inner electrode where primary ionization takes place. Positive ions created in this region move to the larger outside unipolar region to attach themselves to submicron particles. These charged particles are then forced from the charged chamber at which time they may either impinge on the collection electrode to create a measurable axial current or the particles may enter a size discrimination chamber. Should they enter this discrimination chamber, particles of a given mobility or size are collected by two additional concentric cylindrical electrodes.

Sub-micron particle detector

Growing community of inventors

Pittsburgh, PA, United States of America

Charles D Litton