Abstract: In a first mode, a monitoring system inputs humidified gas through at least a portion of a conduit. At least a portion of the water in the humidified gas adheres to the inner surface of the conduit, inhibiting contaminants in the gas sample from adhering to the inner surface. The water in the humidified gas may also push any contaminants adhered to the surface of the sample line back out the sample line. In a second mode, after previously passing the humidified gas through the conduit, the monitoring system controls a flow of a gas sample including the contaminants through the conduit to a gas analyzer. The one or more layer of water on the inner surface of the conduit prevents or reduces a buildup of undesirable contaminants on an inner surface of a conduit that conveys gas samples.

Abstract: A portable (handheld) volatile organic compound monitoring system for monitoring, for fugitive emissions, a device that includes a coded identification tag. The system includes a housing, a tag reader, analysis chamber structure, a sample probe coupled to the analysis chamber, and pump structure for drawing a gas sample to be analyzed through the sample probe into the analysis chamber. Ionization apparatus is coupled to the analysis chamber for ionizing a gas sample drawn into the analysis chamber from the device being monitored, and a sensor responsive to ionized gas in the chamber produces an output signal as a function of an ionization characteristic of the ionized gas. First storage stores a plurality of response factors as a function of various types of volatile organic compounds to be monitored, second storage stores tag information read by the tag reader, and circuitry responsive to tag information stored in the second storage selects a response factor from the first storage.

Abstract: A hot film dual element fluid flow sensing device has its two hot-film sensors arranged in-line on an elongate support. A flow deflection collar is situated midway on the support between the two flow sensors and deflects the flow away from the sensor situated behind the collar. Underlying the sensor films of the two flow sensors and electrically insulated from those sensor films is an electrical heater. In operation of the device, the heater and the sensor films are electrically heated to about the same temperature to inhibit heat transfer therebetween. Because of that arrangement, the device responds rapidly to changes in fluid flow because virtually all the heat lost by the sensor films is transferred directly into the surrounding fluid.

Abstract: A fluid flow sensor apparatus for determining speed, mass flow and direction of motion relative to a fluid in which the sensor is immersed. The sensor is constructed of at least two spaced apart resistive electrical conductors which are mechanically supported to provide a degree of thermo isolation between the conductors in order to effect the determination of instantaneous fluid flow direction. A pair of the conductors is joined so that the flow around separate conductors is avoided so as to force one conductor to be a leading edge to the flow stream and the other conductor to be a trailing edge, with separate flow passing over the conductor pair. The electrical conductors can be wires or they can be metallic or resistive films which are deposited on a supporting body. The conductor is made of a material which exhibits a change in the electrical resistivity as a function of temperature.