Abstract: A sterile device immersed in a sterile buffer and a method for providing same. The sterile device may be a medical device such as a biosensor having a biomolecule as a sensing element such as, for example, a glucose oxidase enzyme. The buffer may be a bicarbonate solution. Both the device and the buffer may be packaged and stored over long term while maintaining sterilization. The sterilization method may comprise a combination of gaseous, liquid and light sterilization.

Abstract: A Chemical Detector, a training method and a method for detecting a chemical or chemicals has been developed that uses invertebrate organisms trained to respond to targeted chemical odors.

Abstract: A method and apparatus for sensing a flammable vapor are described herein. Initially, a first thermal conductivity of a vapor at a first temperature and a second thermal conductivity of the vapor at a second temperature can be determined. Thereafter, a ratio of the first thermal conductivity signal to that of the second thermal conductivity can be calculated to obtain a primary “vapor” signal. The “vapor” ratio can then be compared to an “air” ratio of air without the vapor at the first temperature and the second temperature to obtain a secondary signal thereof. Such a secondary signal can then be compared to an alarm set-point value to thereby determine whether the vapor comprises a flammable vapor and a risk-reducing action thereof be taken.

Abstract: A microelectromechanical heating apparatus and fluid preconcentrator device utilizing same wherein heating elements of the apparatus are sized and spaced to substantially uniformly heat a heating chamber within a heater of the apparatus. Tall, thermally-isolated heating elements are fabricated in Si using high aspect ratio etching technology. These tall heating elements have large surface area to provide large adsorbent capacity needed for high efficiency preconcentrators in a micro gas chromatography system (?GC). The tall heating elements are surrounded by air gaps to provide good thermal isolation, which is important for a low power preconcentrator in the ?GC system.

Abstract: Intended for application on ducts through which flow a fluid at a high temperature, and particularly at a high pressure, comprising two bodies (4) and (8) which axially screw onto each other, one body (4) provided with a threaded neck (5) for attachment to the orifice of duct wall (3), which body (4) houses within it sensor element (2) of the probe which is thus placed inside the duct, with second body (8) screwed onto first body (4) and exerting on sensor element (2) the pressure required to secure it in its housing, with second body (8) further provided with an axial orifice through which passes a metallic tube (9) open to the exterior and which is provided with a metallic washer (10), soldered to said tube (9), which is separated from second body (8) by an electrically insulating washer (12).

Abstract: A combustible gas sensor includes an active element in electrical connection with a measurement circuit. The measurement circuit includes a thermistor network to compensate for the effect of changes in ambient temperature to the resistance of the active element. Another combustible gas sensor includes an active element having a geometric surface area no greater than approximately 0.5 mm2 in electrical connection with a measurement circuit. The measurement circuit includes a compensator that compensates for the effect of changes in ambient temperature to the resistance of the active element without compensating for heat lost by thermal conduction from the active element.

Abstract: The present invention provides an ozone detecting material comprising a polymer prepared by polymerization of at least one monomer selected from the group consisting of 2-, 3-, 4-halogen substituted anilines or aniline substituted with C1-3-alkyl in N-position, and diphenylamine, formed into a thin film coated on a transparent substrate, waveguide, or optical fiber, or additionally comprising a component selected from electro-conductive fine carbon powder, a semiconductive metal oxide, or a semiconductive polymer material, and a method for detecting ozone comprising the steps of contacting this ozone detecting material with an ozone-containing gas and determining the light absorption rate and/or electrical conductivity of the ozone detecting material at that time.

Abstract: An electronic system for selectively detecting and identifying a plurality of chemical species, which comprises an array of nanostructure sensing devices, is disclosed. Within the array, there are at least two different selectivities for sensing among the nanostructure sensing devices. Methods for fabricating the electronic system are also disclosed. The methods involve modifiying nanostructures within the devices to have different selectivity for sensing chemical species. Modification can involve chemical, electrochemical, and self-limiting point defect reactions. Reactants for these reactions can be supplied using a bath method or a chemical jet method. Methods for using the arrays of nanostructure sensing devices to detect and identify a plurality of chemical species are also provided.

Abstract: A chemical-sensing apparatus is formed from the combination of a chemical preconcentrator which sorbs and concentrates particular volatile organic chemicals (VOCs) and one or more chemiresistors that sense the VOCs after the preconcentrator has been triggered to release them in concentrated form. Use of the preconcentrator and chemiresistor(s) in combination allows the VOCs to be detected at lower concentration than would be possible using the chemiresistor(s) alone and further allows measurements to be made in a variety of fluids, including liquids (e.g. groundwater). Additionally, the apparatus provides a new mode of operation for sensing VOCs based on the measurement of decay time constants, and a method for background correction to improve measurement precision.

Abstract: Sensors and methods of monitoring for the presence of gas phase materials by detecting the formation of films based on the gas phase material are disclosed. Advantageously, some gas phase materials preferentially deposit on specific surfaces. As a result, selective detection of those gas phase materials can be obtained by detecting films deposited on those detection surfaces. Examples of gas phase materials that may be detected include RuO4, IrO4 and RhO4.

Abstract: An A/F signal proportional to an oxygen concentration in the exhaust gas from an internal combustion engine is output upon application of a voltage based on an instruction from a microcomputer. At the time an element resistance is detected, a bias instruction signal Vr from the microcomputer is converted by a D/A converter 21 to an analog signal Vb. An output voltage Vc obtained by removing high frequency components from the analog signal Vb through an LPF 22 is input to a bias control circuit 40. During this time period in which the element resistance is detected, an accurate A/F signal is not output. Therefore, the A/F signal that has theretofore prevailed is held by a Sample/Hold circuit 70 to thereby prevent the use of an erroneous A/F signal. Namely, at the time of detecting the element resistance, the detected value of the oxygen concentration is prevented from becoming abnormal. As a result, an accurate A/F control can be executed using the detected element resistance.

Abstract: A sensor for detecting a target matter includes a chemical sensitive layer that is operable to react when exposed to the target matter and a piezoresistive material coupled to the chemical sensitive layer. The chemical sensitive layer is configured such that the reaction of the target matter with the chemical sensitive layer creates an interfacial tension at the interface of the chemical sensitive layer and the piezoresistive material that changes the electrical resistance of the piezoresistive material. However, the chemical sensitive layer is configured such that the reaction of the target matter with the chemical sensitive layer does not affect the bulk properties of the chemical sensitive layer enough to change the electrical resistance of the piezoresistive material. The sensor also includes an electrical circuit coupled to the piezoresistive material that is operable to detect the change in the electrical resistance of the piezoresistive material due to the interfacial tension.

Abstract: A biosensing cell assembly having a measurement loop with a test cell having an analyte reaction zone for amperometric measurement of a response current to determine analyte concentration and a noise cancellation loop arranged to be physically exposed to the same electromagnetic environment as the measurement loop. The noise cancellation loop has a predetermined impedance within a range of the impedance of the test cell analyte reaction zone and provides a current to cancel or reduce the effects of the electromagnetic environment on the measurement loop.

Abstract: Disclosed herein is a method and apparatus for analyzing, sensing and measuring information related to the concentrations of various gases, including NOx, hydrocarbons, carbon monoxide and oxygen, in a multi-component gas system using chemical sensors and chemical sensor arrays. The sensors and sensor arrays use chemo/electro-active materials to analyze and detect the presence of gases.

Abstract: The measuring sensor, particularly a lambda probe, has a ceramic sensor member retained at a high temperature during measuring operation. It is shielded from water droplets, carried along in the gas to be analyzed, by a heated protective housing, permeable for the gas to be analyzed, by which water droplets carried along in the direction of the sensor member are evaporated before reaching the sensor member. In this way, the water droplets are unable to cause any shock-like temperature drops at spots on the surface of the sensor member or material flaking.

Abstract: A magnetic sensing element detects the presence of magnetic particles in a binding assay. The magnetic sensing element has at least one planar layer of electrically conductive ferromagnetic material that has an initial state in which the material has a circular magnetic moment within the plane of the layer. The magnetic sensing element has molecules of a first specific binding member attached to it. The device also includes a fluid test medium to which the magnetic sensing element is exposed during the course of a binding assay. The fluid test medium includes magnetizable particles that become immobilized during the assay in relation to the amount of analyte in the test medium.

Abstract: The present invention relates to methods for matching and validating the response intensity of a sensor array to an odorant with the detection threshold of a human nose.

Abstract: Biochemical devices comprising a sensing surface that is at least partially covered by a nanocrystalline metal oxide semiconductor film which provides a recipient surface for immobilizing biochemical species on. The film has a mesoporous surface that gives up to a 1000 increase in biochemical species adsorption when compared to a flat surface. The biochemical devices comprising these surfaces can be optical and electrochemical biosensors and reactors for synthetic or biodegradation reactions.

Abstract: An improved, affordable, and rapid fluid mixture composition or process monitor based on a thermal microstructure sensor. This is preferably accomplished with a microbridge sensor design that has reduced susceptibility to interfering components of the mixture. The sensor described herein is therefore suitable for monitoring the concentration of at least one component in a fluid mixture when the fluid mixture consists of either (1) two components with very different thermal conductivities; or (2) three or more components wherein at least one component has a very different thermal conductivity and the effects of the other components can be largely eliminated, especially if the component of interest is hydrogen and the interference is from the variability in the concentrations of CO2 and H2O.

Abstract: A method and apparatus is provided for an electrochemical cell system. The electrochemical cell system includes: an electrochemical cell; an energy source configured for providing a quantity of energy to the electrochemical cell; a sensing apparatus in operable communication with a gas output from the electrochemical cell, the sensing apparatus provides an output signal indicating a parameter of the gas output; and a computer in operable communication with the sensing apparatus. The computer includes a memory device configured to store a first operational parameter, and a processor configured to receive a digital representation of the output signal and the first operational parameter. The processor compares the digital representation of the output signal to the first operational parameter for regulating the quantity of energy provided to the electrochemical cell.

Abstract: Field-effect transistor (FET) devices with carbon nanotubes as the conducting channel detect chemicals in liquids are described. Chemical detection occurs primarily through analysis of conduction (l) as a function of the applied gate voltage (Vg). The conductivity of liquids is an important variable in the analysis of measurements of the device performance. In high-conducting liquids, screening and liquid conductance dominate in the device measurements; in low-conductive liquids (e.g., cyclohexane), the changes in the NTFET device performance upon exposure to different chemicals are similar to those found for the performance of the device in a gaseous environment. The influence of aromatic compounds on the device electronics can be correlated with their relative ability to donate or withdraw electrons from the carbon nanotube. A shift in the threshold of l-Vg was found to be linear with Hammett sigma values (&sgr;p) for mono-substituted benzene compounds.

Abstract: The present invention provides an oxidation sensor for an electrical circuit or MEMS device that includes a conductor located on an insulating substrate and a sensor trace located on the insulating substrate adjacent the conductor. The sensor trace is located on the insulating substrate adjacent the conductor and is configured to oxidize at a rate greater than an electrical component associated with the sensor trace on the electrical circuit or MEMS device when the sensor trace and the electrical component are exposed to a same oxidizing environment. By oxidizing and thus becoming an open circuit more rapidly than any structure on a electrical circuit or MEMS device at a given relative humidity (i.e. in the same package), the oxidation sensor is designed to provide early warning of oxidation. Thus, the present invention serves as a sensor that will give advance warning of a leaky package and associated oxidation.

Abstract: A gas sensor including: an insulating substrate; a pair of thin film electrodes provided on the insulating substrate in such a manner as to leave a fixed space between them; a gas sensitive film including a metallic oxide which is provided in such a manner as to substantially fill at least the fixed space left between the electrodes; and a catalytically active protective layer formed in such a manner as to cover the surface of the metallic oxide exposed to the outside.

Abstract: A layered composite with a gas-sensitive layer (15) and a catalytically active layer (16), joined materially to it at least in some regions, is provided, in which the gas-sensitive layer (15) has a first material and the catalytically active layer (16) has both the first material and a catalytically active additive. It is also provided that the specific electrical resistance of the catalytically active layer (16) is higher than that of the gas-sensitive layer (15). In addition, a micromechanical sensor element (5), in particular a gas sensor element, with a dielectric layer (11), a gas-sensitive layer (15) disposed on the dielectric layer, and means (14) for detecting a change in the electrical conductivity of the gas-sensitive layer (15) under the influence of a gas is proposed.

Abstract: A molecular recognition sensor system for detecting the presence and concentration of an analyte including a resistive sensor having a semiconductive polymer film which swells when exposed to an analyte and interferents and a molecular imprinted resistive sensor having a semiconductive polymer film imprinted with the analyte which thereby swells when exposed to interferents, a circuit connected to the resistive sensor and the molecular imprinted resistive sensor for detecting a change in the resistance of the resistive sensor when exposed to the analyte and the interferents, the change in the resistance of the molecular imprinted resistive sensor when exposed to the analyte and interferents, and for subtracting the change in resistance of the molecular imprinted resistive sensor from the change in resistance of the resistive sensor to reduce the effect of any interferents on the change in resistance of the resistive sensor thereby determining the presence and concentration of the analyte.

Abstract: A diagnostic system for monitoring catalyst performance in an exhaust system comprises a plurality of treatment devices catalytically treating an exhaust gas stream, and a plurality of gas sensors for monitoring the catalyst performance of the treatment devices to determine when sulfur poisoning occurs. An on-board diagnostic system receives signals from the gas sensors, and, based upon response time differentials between sensors, determines whether the treatment devices are experiencing sulfur poisoning.

Abstract: The present invention provides an apparatus and method of reducing noise associated with biomolecular measurement systems. Sensor detection system noise characteristics in the presence of other sensor detection systems are determined and advantageously used to determine an arrangement of the individual sensor cells. The sensor cells are arranged on a substrate such that the system noise is determinable and can thus be filtered from the measurement signal.

Abstract: A gas sensor comprising a sensor element including an organic-inorganic hybrid material. The sensor element has layers of an inorganic compound and an organic compound intercalated between the layers of an inorganic compound.

Abstract: A gas sensor (22) for detecting the presence of a selected component in a gas (41) includes a substrate (28) exhibiting a low thermal resistance. A heater element (34) is disposed substantially over a surface area of a first surface (30) of the substrate (28). Sensor and reference elements (36, 38), formed from a single metal trace (54), are disposed on a second surface (32) of the substrate (28). The electrical resistivity of the sensor element (36) changes as the sensor element (36) adsorbs molecules of the selected component. During a regeneration process, the heater element (34) is activated to provide substantially even heating over the surface area of the first surface (30). Heat from the heater element (34) conducts through the substrate (28) to heat the sensor element (36) and the reference element (38) to a regeneration temperature sufficient to cause the adsorbed molecules of the selected component to be liberated.

Abstract: An ionisation detector includes a third (fence) electrode (55) between the counter electrode (53) and the sensing electrode (54). The fence electrode (53) is maintained at or near the potential of the sensing electrode (54) and traps charge movement (electrolytic current) along the detector walls associated with condensation and/or contamination within the detector. In a photoionisation detector, the fence electrode is also adapted to trap photo-induced current originating from the cathode (53).

Abstract: Devices and methods are disclosed that are effective to produce reliable vapor measurements in the presence of drift. In certain instances the sensor module is mounted externally on a housing. In other instances, the sensor module contains a first sensor element incorporating a first array of sensors and a second sensor element incorporating a second array of sensors wherein both sensor elements are mounted externally on the housing. In other embodiments, the present invention relates to mapping an x-y surface for detection of an analyte, the method includes moving in tandem at least two sensor arrays separated by a distance “d” across an x-y surface to produce a plurality of responses and analyzing the responses to map the x-y surface for detection of an analyte. Moreover, the present invention provides a sensor module, such as in a handheld device, comprising at least two pneumatic vapor paths and at least two sensor arrays.

Abstract: Sensor arrays, methods, and systems for detecting the presence of gas phase materials by the formation of films based on the gas phase material are disclosed. The gas phase materials preferentially deposit conductive films on receptor materials that can be detected. The invention may also provide for increased sensitivity to the deposition of conductive materials through the use of closely spaced conductive electrodes interconnected by lines of receptor material. Examples of gas phase materials that may be detected include RuO4, IrO4 and RhO4.

Abstract: An apparatus, system and method maximizes efficiency and accuracy of measuring an oxygen concentration of a measured gas by varying a flow of oxygen ions within a measuring cell (202) in accordance with an output signal of an oxygen sensor cell (206). The pump current (208) through a pump cell (204) is switched between a constant positive current and a constant negative current when upper and lower thresholds of the output signal are reached. The pulse width ratio of the square wave produced by the varying current is compared to a pulse width ratio function derived from a calibration procedure to determine the oxygen concentration of the measured gas.

Abstract: A method of making a high efficiency magnetic sensor for determining the presence or amount of an analyte in a test sample. The method typically includes providing a sensing device with a magnetic sensing element, exposing the sensing device to a fluid test medium suspected of containing an analyte and monitoring the resistance of the magnetic sensing element to detect any change in the electrical resistance of the magnetic sensing element in response to the immobilization of a magnetizable particle. The magnetic sensing element comprises at least one planar layer of electrically conductive ferromagnetic material having an initial state in which the material has a circular magnetic moment within the plane of the layer, a means to immobilize a magnetizable particle at a point along an axis that is perpendicular to the plane of the layer and passes through the center of the circular magnetic moment, and a means for detecting the change in the electrical resistance of each magnetic sensing element.

Abstract: Chemical sensors for detecting the activity of a molecule or analyte of interest is provided. The chemical sensors comprise and array or plurality of sensors that are capable of interacting with a molecule of interest, wherein the interaction provides a response fingerprint. The fingerprint can be associated with a library of similar molecules of interest to determine the molecule's activity and diffusion coefficient.

Abstract: An electro-chemical analysis device and method for analyzing biomolecular samples, including a means for holding a sample on a substrate platform, a thermal sensor, a biosensor formed having a specific spatial resolution as related to the thermal sensor, and a means for providing radiation to the biomolecular sample. The means for holding the sample, the thermal sensor, the biosensor, and the means for providing radiation all three-dimensionally integrated with the substrate platform, thereby defining a compact biomolecular analysis device having a volume resolution of less than 50 micro liters. During operation, radiation is provided to the biomolecular sample to provide for a constant temperature at which hybridization of the biomolecules takes place. The temperature of the biomolecular sample is monitored and controlled by the integrated thermal sensor and the integrated heater. Once hybridization takes place, the change in electric condition (e.g.

Abstract: A gas sensor for the detection of gases comprises a housing and an active element disposed within the housing. The active element is surrounded by a porous insulating material having a bulk density no greater than 0.15 g/cc. Another gas sensor comprises an active element surrounded by a porous insulating material having a surface area no greater than approximately 200 m2/cc. Another gas sensor comprises a copper compound positioned so that gas contacts the copper compound before contacting the active element. Another gas sensor comprises an active element surrounded by a porous material having an average pore size of at least approximately 100 Å. Another gas sensor comprises a heating element surrounded by a porous material that supports a catalyst.

Abstract: This invention relates to a novel class of vapor sensors with tunable properties. More particularly, this invention relates to vapor sensors modified by the addition of a compatible small molecule of low volatility, i.e., a plasticizer. In certain aspects, the invention relates to a sensor for detecting an analyte in a fluid comprising: an organic polymer; a plasticizer combined with the organic polymer; and detector operatively associated with the organic polymer.

Abstract: Techniques are used to detect and identify analytes. Techniques are used to fabricate and manufacture sensors to detect analytes. An analyte (1810) is sensed by sensors (1820) that output electrical signals in response to the analyte. The electrical signals are preprocessed (1830) by filtering and amplification. In an embodiment, this preprocessing includes adapting the sensor and electronics to the environment in which the analyte exists. The electrical signals are further processed (1840) to classify and identify the analyte, which may be by a neural network.

Abstract: A robust single-chip hydrogen sensor and a method for fabricating such a sensor. By utilizing an interconnect metallization material that is the same or similar to the material used to sense hydrogen, or that is capable of withstanding an etchant used to pattern a hydrogen sensing portion, device yields are improved over prior techniques.

Abstract: A hydrocarbon detector (20) includes a gas stream delivery element (26) configured to discharge a carrier gas (70) onto a surface (24). The carrier gas (70) serves to volatilize a hydrocarbon presence (22) from the surface (24). A gas stream recovery element (28) is configured to aspirate a sample gas (78) formed from the carrier gas (70) combined with the hydrocarbon presence (22) volatilized from the surface (24). A hydrocarbon sensor (58) detects the hydrocarbon presence (22) in the sample gas (78) and generates an output signal indicative of the hydrocarbon presence (22). An indicator (80) receives the output signal and indicates the hydrocarbon presence (22) in the sample gas (78). A heat source (72) coupled to the gas stream delivery element (26) heats the carrier gas (70) to further aid in the volatilization of the hydrocarbon presence (22).

Abstract: A method is provided for continuously monitoring for the presence or quantity of an analyte in a flowing liquid stream. The method involves binding an analyte-specific receptor species to the surface of a piezoelectric substrate, contacting the surface bound receptor species with the flowing liquid stream and quantitating the presence of the analyte. A novel apparatus for detecting the presence of an analyte in a liquid chromatography eluant is provided as well.

Abstract: A semiconductor device (FIG. 1) is provided for the detection of nitric oxide (NO) molecules in gaseous mixtures, in biological fluids and in aqueous solutions. The device is a molecular controlled semiconductor resistor (MOCSER) of a multilayered GaAs structure to which top layer a layer of multifunctional NO-binding molecules are adsorbed. The sensitivity of the semiconductor device towards NO is independent of mixture composition. Nitric oxide concentrations of as low as 10 ppb NO were detected in mixtures containing various contaminants.

Abstract: An exhaust gas sensor includes a housing and a sensor element supported by the housing. The sensor element includes a support member having an exhaust side, a reference side, and an aperture extending through the support member between the exhaust side and the reference side. The sensor element further includes an exhaust-side electrode on the exhaust side of the support member. The exhaust-side electrode is electrically connected to a contact on the reference side of the support member via a lead extending through the aperture. The aperture is sealed around the lead such that gas cannot pass through the aperture. The support member is oriented substantially parallel to the flow of exhaust gases when the exhaust gas sensor is installed on a vehicle. The sensor further includes a contact pin in the housing that engages the contact and biases the sensor element against a portion of the housing.

Abstract: A sensor array 120 contains two chemiresistor which generate a response 130 in the presence of an analyte. The response is detected using an infrared detector 135, such as an infrared camera The infrared detector 135 generates a thermographic image 140 for each sensor in the array. The thermographic image 140 contains a matrix of responses 150, 160 for each sensor.

Abstract: The analytical process utilized in the system of this invention comprises three (3) step distinct steps wherein an analyte of interest in a test sample is initially labeled and subsequently isolated within a porous medium of a test device. Once isolated within the medium, the label is displaced from the analyte, or from the complex with the analyte, and converted, under electrolytic condition, to a metallic species which is caused test to deposit upon a working electrode of the test device. This working electrode is part of an electrode array that is positioned coincident with the porous medium, yet maintained physically remote therefrom. This deposit is then stripped from the working electrode, under anodic stripping conditions, and the current generated within the electrode array monitored. The characteristic response curve that is produced thereby can be correlated with the identity and concentration of the analyte(s) with the test sample.

Abstract: A device and a method for simply and accurately evaluating performance of fuel cells have been provided. Hydrogen gas and carbon monoxide gas are caused to flow into a sample holder where an electrode catalyst sample is laid, and the amount of carbon monoxide gas discharged therefrom is detected. The amount of carbon monoxide gas adsorbed by the electrode catalyst sample is calculated based on the amount of supplied carbon monoxide gas and the amount of detected carbon monoxide gas. The output voltage of a fuel cell is calculated based on a correlation between calculated amounts of carbon monoxide gas adsorbed by the electrode catalyst and output voltages of the fuel cell.

Abstract: A polymeric gas sensor utilizes a variety of electrode geometries to generate varied responses to selective gases. The characteristic response to various gases of each electrode geometry permits the construction of a gas sensor having desirable and reproducible characteristic responses to specific gases. The gas sensor array of the invention produces characteristic responses from a plurality of sensors. These responses collectively produce a characteristic response pattern that can be used for the identification of specific gases with pattern recognition techniques.

Abstract: A vehicle exhaust analyzer module including a housing enclosure having symmetrical portions secured together, a support shelf supported within the housing enclosure, a gas inlet for directing gaseous vehicle exhaust into the housing enclosure, a sensor assembly positioned on the support shelf for receiving the gaseous vehicle exhaust and providing an analysis of the gaseous vehicle exhaust, circuitry for controlling the sensor assembly, and a signal output connector coupled to the control circuitry for outputting a signal representing an analysis result of the sensor assembly.

Abstract: Methods automatic process control of biasing and testing a heated-electrode refrigerant sensor for use in a refrigerant detector. An unbiased sensor may be mounted in a manufacturing station, and while mounted may be biased by applying current to electrically heat the sensor and by applying a voltage potential between the sensor's anode and cathode, thereby generating a bias current at the cathode, and after the sensor is at least partially biased, the bias current is used to electrically test the sensor's construction. If the temperature of the sensor is held constant at a bias temperature, the acceptability of the sensor may be determined based on the time that elapses before the bias current decreases from an initial value to a threshold value, or determined based on the noise present on a signal which is representative of an operating condition other than the bias current magnitude.