Abstract: A system and method for inferring the feeder and phase of a transmitter on a plurality of electrical distribution lines. The system may include a low-voltage electrical distribution grid having one or more phases and one or more lines, a mechanism for transmitting a measuring data, a mechanism for receiving the measuring data, and a mechanism that analyzes the transmitted data to infer the phase and feed on which the transmission is injected.

Abstract: A system and method for measuring particulate concentrations. The system includes a substantially planar, peripherally supported filter for capturing the particulates, an oscillator for oscillating the filter substantially perpendicular to its planar surface, and a sensor for measuring the frequency of oscillation.

Abstract: A system and method for determining airborne particle concentrations. When in a fixed time period mode of operation, the system determines actual airborne particle concentration when a normal particle count is detected, and determines an "upper limit" particle concentration based on Poisson statistics when a low particle count is detected. In a fixed precision mode of operation, the system determines in advance the number of particles needed to be detected to achieve an airborne particle concentration measurement having a precision equivalent to a user selected fixed precision, and prints out airborne concentration measurements only when such measurements have the user selected fixed precision.

Abstract: A real time asbestos aerosol monitor and method are provided. An ambient air sample is passed through a first sensing zone where fibers in the sample are electrically aligned and oscillated as they are illuminated perpendicular to the fiber axes with high intensity laser light. The scattered light signal pulse train from a first detector is analyzed to determine the presence and size of fibers in the sample. The air sample is then passed through a second sensing zone including a hybrid electric/magnetic field to electrically align and magnetically oscillate asbestos fibers. The sample in the second sensing zone is illuminated perpendicular to the fiber axes, with the scattered light signal pulse train from a second detector being analyzed to determine whether each fiber detected in the first sensing zone is an asbestos fiber. Advantageously, clean air is circulated across illumination optical surfaces to protect against abrasive elements in the air sample. Zeroing and calibration are also provided.