Abstract: When a detection signal obtained from the cell of a gas sensor (S15) has reached a start determination value (specifically, when the output voltage of the cell is higher than 600 mV (S16: YES) or lower than 300 mV (S17: YES)), a pulse voltage is applied to the cell (S18), and a start-time internal resistance is obtained on the basis of the detection signal having changed as a result of application of the pulse voltage (S20). The start-time internal resistance is compared with a deterioration determination value set in advance (S21). A target resistance of the cell used in temperature control (energization control) for the heater is corrected in accordance with the result of the comparison (S28). Thus, the temperature of the cell can be stably maintained constant irrespective of deterioration of the cell.

Abstract: Methods and systems are provided for accurately learning the zero point of an intake gas oxygen sensor in varying ambient humidity conditions. The learned zero point is corrected based on an estimated ambient humidity to calibrate the reading for dry air conditions or standard humidity conditions. EGR control is performed by comparing the output of an intake oxygen sensor during EGR conditions relative to the humidity-corrected zero point.

Abstract: A method for measuring the concentration of a gas component in a measurement gas using a gas analyzer comprises varying the wavelength of the light of a wavelength-tunable light source within periodically consecutive scan intervals for wavelength-dependent scanning of a gas component absorption line of interest. The method also comprises modulating the wavelength of the light of the wavelength-tunable light source with a frequency, guiding the modulated light through the measurement gas onto a detector and demodulating a measurement signal generated by the detector in the event of a harmonic of the frequency. The method further comprises producing a measurement result by fitting a desired curve to the profile of the demodulated measurement signal. A function orthogonal to the desired curve is provided, and an orthogonal component of the measurement result is produced by fitting the orthogonal function to the profile of the demodulated measurement signal.

Abstract: A method and apparatus for background cancellation for electronic noses to make automated aroma analysis practical in complex field environments. The system and methods compensate for background contaminants while automatically emphasizing all constituents, be they chemically identified or not, which represent information content in the sample being tested.

Abstract: An apparatus for cleaning a detector comprising a housing and a bowl connected to the housing having a detector chamber adapted for enclosing a detector to be cleaned, a contacting surface positioned on the bowl, and one of more air nozzles positioned within the detector chamber for directing one or more bursts of compressed air at a detector to clean the detector, and a fan positioned within the housing operable to draw air within the detector chamber into a filter, and a dust collector for containing dirt and debris dislodged from a detector during the cleaning operation.

Abstract: Apparatus for testing a hazard detector, the apparatus comprising electrically-powered generating means arranged to generate at least two stimuli for application to the detector; and control means arranged to control the generation of each stimulus by said stimulus generating means, wherein said generating means includes a carbon monoxide generator.

Abstract: A system for improving operation of an engine having a particulate matter sensor is presented. The system may be used to improve engine operation during cold starts especially under conditions where water vapor or entrained water droplets are present in vehicle exhaust gases. In one embodiment, particulate sensor degradation is indicated in response to an output of said particulate matter sensor staying below a threshold as engine temperature increases past the dewpoint temperature.

Abstract: A method for determining a polarization of a pump cell and/or a Nernst cell of a lambda probe for the diagnosis of the broadband lambda probe. A voltage or current pulse is applied to the pump/Nernst cell in a first method task, and, in a second method task, a voltage at the pump cell and/or the Nernst cell, or a variable that is related to the polarization or its time characteristic is determined and used as a measure of the polarization, and the function of the broadband lambda probe is monitored via the ascertained polarization. The determination of the polarization may be performed as a voltage measurement performed once or multiple times, or by determining the effect of the polarization in an associated controller, such as a pump current controller of an engine control unit. The variable associated with the polarization may be the reaction of the pump current control.

Abstract: A method and system for detecting, quantifying or characterizing emitting sources. According to an embodiment, an emission source is located by monitoring an area with one or more sensors, determining a plume, generating one or more candidates for the emission source, and using the plume to derive one or more characteristics associated with the emission source, and then locating the emission source based on agreement or convergence of the one or more characteristics.

Abstract: A measured value of a sensor element is obtained during repeatedly executed measuring periods for performing different measurements and for setting different operating states, the sensor element being electrically connected in a periodically alternating manner, in consecutive switching positions, in a predefined order, where at least one measurement for determining the measured value is performed repeatedly within a measuring period for determining individual values at predefined switching positions, the measured value being determined from the individual values. Using the switching position within the measuring period, the operating state of the sensor element preceding the individual measurement, and therefore, the influence of the preceding circuit configuration on the individual measured value, is known, and the individual values are correspondingly corrected. By correcting the individual values, the measured value determined from the individual values is also corrected.

Abstract: A photoacoustic detector wherein control circuits compensate for long term variations of components therein including a light source and sensing microphones. The control circuits intermittently energize the source to evaluate changes in at least source resistance. The control circuits intermittently energize an acoustic generator to evaluate changes in one or more generator responsive microphones.

Abstract: A test station for a plurality of test gases, includes a main unit (10) with a control (12) and test modules (20), each for a gas measurement device, that exchange data to register a type of gas measurement device and test gas(es) required for the device type. The control sets a schedule for a test using a test gas, or for a plurality of successive tests each with different test gases and carries out the specific test planned according to the schedule, in parallel with tests for all of the test modules for a test gas and determines, as an additional gas measurement device is inserted, based on the particular device type of the additional gas measurement device, whether the currently-running test with the current test gas is suitable for the inserted test module; and if the test gas is suitable, to start the test for this test module.

Abstract: A gas-solution equilibrium device for a liquid sample gas analyzer includes a temperature-controlled, thermally-conductive mandrel, a coil of gas-permeable tubing wrapped around the mandrel, the gas-permeable tubing having an inlet and an outlet, and a housing having an internal space containing the temperature-controlled, thermally-conductive mandrel, the coil of gas-permeable tubing and a volume of gas where the gas-permeable tubing has a predefined linear length and a predefined wall thickness, the combination of which together is capable of equilibrating a liquid passing through the coil at a predefined flow rate with oxygen in the atmosphere to provide a gas calibration solution in real time at the outlet of the tubing for the liquid gas analyzer.

Abstract: An electrolytic gas sensor which is sensitive to a specific gas and has a working, reference and counter electrode is functionally monitored. A differential voltage between the reference and working electrodes is amplified and the potential of the counter electrode is regulated to minimize the differential voltage. Then a measured current flowing into the counter electrode approximately proportionally to the gas concentration of the gas to be detected arises. Independently of the determination of the gas concentration, a working, counter and reference voltage which is present at the three electrodes in each case is captured and monitored for an impermissible deviation. In an impermissible case an assigned error message is then output. Online monitoring of the gas sensor is thus possible and no interruption of the measurement operation for test purposes and additional components are required.

Abstract: A gas sensor which works according to the principle of thermal conductivity is functionally tested. In the method, a calibration cycle is conducted in which a membrane of the gas sensor is immersed in a fluid calibration medium having a known concentration of a target gas. After the calibration cycle, a measurement chamber of the gas sensor is purged with a purging gas. Then, a measuring cycle is conducted, using a thermal conductivity sensor to measure the target gas in the measurement chamber. Using a calibration baseline established from the calibration cycle and a measurement baseline in the measurement cycle, a baseline comparison value is obtained and compared to a predetermined baseline threshold value. An error message, indicating a malfunction in the purging gas supply, is generated when the baseline comparison value exceeds the predetermined baseline threshold value.

Abstract: A gas application device (2) for gas measuring apparatuses (5) has a test chamber device (58) for providing a test gas. A predetermined positive pressure is applied in the line system that connects the test chamber device (58) to one or more test-gas containers (PG) such that a constant test-gas supply (flow) to the test chamber device (58) can be ensured. A method for testing gas measuring apparatuses (5), and a calibration measuring apparatus for testing and calibrating gas measuring apparatuses (5) are also provided.

Abstract: Methods and systems for calibrating a chemical sensing system are disclosed. Detection of a substance using a first chemical sensor in a chemical sensing system may be initiated at a first time. The first chemical sensor may output a first sensor value. Detection of the substance using a second chemical sensor in a chemical sensing system may be initiated at a second time that differs from the first time by a delta value. The second chemical sensor may output a second sensor value. The chemical sensing system may be calibrated based on the first and second sensor values at the second time and the first and second sensor values at a current time.

Abstract: There is provided a portable electronic device with one or more integrated ambient sensors, such as temperature or humidity sensors, for measuring an ambient parameter, a display for displaying the parameter or related information and shared by other elements of the device, and a system receiving input relating to internal or external states of the device and generating in response to the input an accuracy measure of the ambient parameter measurement.

Abstract: Methods and systems are provided for an engine coupled temperature-based humidity sensor. Degradation of the humidity sensor may be determined while flowing gasses into an engine intake air downstream of a humidity sensor and upstream of a compressor, indicating humidity sensor degradation when relative humidity readings change by less than a threshold while temperature at the sensor changes greater than a second threshold.

Abstract: A diagnostic method for a capacitive humidity sensor comprising a heater, and a capacitance-sensing element that individually indentifies heater, temperature-sensing element, or capacitance-sensing element degradation. By this method, individual elements of the sensor may be replaced or compensated for to allow for further operation.

Abstract: A test system and a test method adapted for a remote control device are disclosed. The remote control device is electrically connected to gas supply equipment. The gas supply equipment stores gas and is connected to a gas actuating device. A gas detector is near to the gas actuating device. The method includes: providing a test interface, acquiring a gas detector on the test interface and generating a trigger signal to start testing the gas detector; remotely controlling the gas supply equipment to generate high pressure; and controlling the gas actuating device to spew out gas. The method further includes: comparing the concentration of the gas with a stored reference concentration to determine whether or not the gas detector works properly and generating a result.

Abstract: A process gas analysis system is provided. The system includes a probe insertable into a source of process gas and having a distal end and a chamber proximate the distal end. A gas sensor is mounted within the chamber and is configured to provide an electrical indication relative to a species of gas. A diffuser is mounted proximate the distal end of the probe and is configured to allow gas diffusion into the chamber. A source of calibration gas is operably coupled to the probe and is configured to supply calibration gas, having a known concentration of the gas species. Electronics are coupled to the sensor and configured to store a pre-calibration process gas concentration and to measure an amount of time (sensor return time) for the sensor response to return to the pre-calibration process gas concentration. The electronics are configured to compare a measured sensor return time with a known-good sensor return time to provide an indication relative to the diffuser.

Abstract: A heat-generating apparatus includes a frame assembly and a securement assembly carried by the frame assembly. The securement assembly includes a panel member arranged in a first vertical plane for supporting a target material parallel to the first vertical plane. The heat-generating apparatus also includes a heating support assembly adjustably supported by the frame and including at least one heating element arranged in a second vertical plane that is parallel to and offset from the first vertical plane. The heating support assembly is adjustable along a horizontal first adjustment axis that is perpendicular to each of the first and second vertical planes and along a second adjustment axis that is disposed in or adjacent to the second vertical plane.

Abstract: A composition useful as a Reference Standard for measurement of Cetane Number or for use as a standard for determining a Derived Cetane Number consists essentially of a blend of n-hexadecane and 2,2,4,6,6-pentamethylheptane. The disclosed Reference Standards can be used directly as substitutes for blends of n-hexadecane and 2,2,4,4,6,8,8-heptamethylnonane in ASTM D613-10a for determining Cetane Number, or in ASTM D6890, ASTM 07170 or ASTM D7668 to determine a Derived Cetane Number.

Abstract: A test apparatus for evaluating a measuring device for measuring a diffusion capacity of a person's lungs by measuring a change of concentration of a gas species in a mixture, when the mixture is inhaled and subsequently exhaled by a person, wherein the test apparatus includes (a) a port for connecting to the measuring device; (b) a compartment coupled to the port; (c) a circulation circuit configured to circulate gas from the compartment back to the compartment; and (d) a gas species removing element configured to selectively reduce a partial pressure of the gas species at a point in the circulation circuit.

Abstract: A method for operating an oxygen sensor arrangement senses the oxygen in a breathing loop of a breathing apparatus. The sensor arrangement includes a primary oxygen sensor to measure the oxygen in the breathing loop, a secondary oxygen sensor to measure the oxygen in the breathing loop, and a control arrangement to obtain measures from the oxygen sensor. A test channel arrangement provides a first gas having a first fraction of oxygen from a first gas supply to the primary oxygen sensor at a position adjacent to the primary oxygen sensor. A test valve arrangement opens and closes the flow of the first gas through the test channel arrangement. The control arrangement actuates the first test valve arrangement to provide an amount of the first gas to the primary oxygen sensor via the test channel arrangement and obtain measures from the primary and secondary oxygen sensors.

Abstract: A diagnostic method and system is described for diagnosing an operating condition of a conductive particulate matter sensor. The sensor has a substrate with electrical resistance that varies with temperature and two electrodes on the substrate adapted to collect particulate matter between the electrodes, thereby establishing an electrically conductive path through collected particulate matter between the electrodes that can be detected by measuring electrical resistance between the electrodes, Relect. The diagnosis is performed by heating the substrate in the area between the electrodes and using the resistance between the electrodes to determine detecting whether contamination is present on the surface of the sensor. Heat may be maintained on the sensor to attempt to burn off a detected contaminant, and a subsequent resistance reading may be used to determine if the contaminant was successfully burned off.

Abstract: An automatic sensor excitation voltage adjustment feature, a multi-range concentration feature, a single calibration feature and a barrier circuit feature. The automatic sensor excitation voltage adjustment feature includes a transmitter having a transmitter microprocessor that provides an initial voltage to a sensor having a sensor microprocessor. As the voltage changes a correction signal is relayed from the sensor microprocessor to the transmitter microprocessor. The correction signal is used to adjust the voltage applied to the sensor. The multi-range concentration sensor feature includes an amplifier associated with the sensor/microprocessor to create gain settings used to optimize sensor resolution by changing a gain value for the sensor. This enables use of a single sensor for a variety of different concentration ranges.

Abstract: In a method for adjusting a gas sensor having a hollow chamber connected to a measuring gas chamber and having an electrochemical pump cell electrochemically pumping the gas component into or out of the hollow chamber, at least two pumping-in phases are provided in which the gas component is pumped into the hollow chamber by the electrochemical pump cell, and at least two pumping-out phases are provided in which the gas component is pumped out of the hollow chamber by the electrochemical pump cell. On the basis of at least one feature of the pump current during the pumping-out phases (Mout), at least one piece of information for adjusting the gas sensor is generated. A parameter regarding the pumping-in is predefined differently in the at least two pumping-in phases.

Abstract: Active carbon filters and systems that are operative to detect active carbon filter degradations are provided. The active carbon filter can include a carbon filter comprising activated carbon and defining a filter surface; a first piezoelectric wafer active sensor on the filter surface that is electrically isolated from the carbon filter; and a second piezoelectric wafer active sensor on the filter surface that is electrically connected to the filter surface; and an impedance monitoring device electrically connected to the first piezoelectric wafer active sensor and the second piezoelectric wafer active sensor. Methods are also disclosed for determining if any degradation has occurred in an active carbon filter.

Abstract: A system for testing the efficiency of a test HEPA filter, the system comprises a dilution system and a sampling system. The dilution system processes samples collected upstream of the test HEPA filter. The dilution system has a test portion and a calibrated portion. The calibrated portion aids in determining the dilution ratio of the test portion thereby rendering the dilution system self-calibrating. The sampling system receives upstream samples via the dilution system, and downstream samples collected directly downstream of the test HEPA filter. The sampling system incorporates a flow rate balancing system to ensure accurate counts with respect to samples collected upstream and downstream of the test HEPA filter. The sampling system works well with particle counters fitted with relatively weak fans to draw in samples for counting; this is achieved by connecting the sampling system to both the inlet and exhaust outlet of a particle counter.

Abstract: Calibration and accuracy check systems for a chemical sniffer, such as a breath alcohol tester, which utilize the dispensing of droplets with determinable concentration of alcohol and/or other liquids in a determinable number either directly to a reaction chamber, or into a carrier gas which can be sampled. The systems generally provide for accurate sample concentration being provided to the breath tester while also providing for a simplified system which can be easier to move, and require less operational complexity, than prior wet or dry calibrating systems.

Abstract: A system for calibrating a response to an exhaust-stream NOx level in a motor vehicle is provided. The system comprises a NOx sensor that includes an electrode, a current from the electrode responsive to the exhaust-stream NOx level while a bias voltage is applied to the electrode. The system further comprises a controller configured to interrupt the bias voltage and to adjust a motor-vehicle response to the current based at least partly on an attained voltage of the electrode while the bias voltage is interrupted. Other embodiments provide a method of calibrating a NOx sensor response in terms of gain and offset parameters.

Abstract: Provided is an apparatus for detecting cylinder air-fuel ratio imbalance abnormality. The apparatus is provided with an abnormality detecting unit that detects a cylinder air-fuel ratio imbalance abnormality by comparing a value of a parameter correlated with a degree of fluctuation in the air-fuel ratio sensor output to an abnormality threshold value, and a correcting unit that corrects at least one of the value of the parameter or the abnormality threshold value on the basis of atmospheric pressure. An amount of correction performed by the correcting unit is modified according to engine load.

Abstract: An oxygen sensor arrangement is arranged to sense the oxygen in a breathing loop of a breathing apparatus. The sensor arrangement comprises at least one primary oxygen sensor arranged to operatively measure the oxygen in the breathing loop, and a control arrangement for obtaining measures from the oxygen sensor. A test channel arrangement is adapted to operatively provide a first gas having a first fraction of oxygen from a first supply to the primary oxygen sensor at a position adjacent to or directly adjacent to the primary oxygen sensor. A first test valve arrangement is arranged to operatively open and close the flow of the first gas through the test channel arrangement. The control arrangement is arranged to operatively actuate the first test valve arrangement so as to provide an amount of the first gas to the primary oxygen sensor via the test channel arrangement.

Abstract: A method for measuring and/or calibrating a gas sensor for determining oxygenic gas components in gas mixtures in exhaust gases of internal combustion engines. The gas sensor has one internal pump electrode IPE, one external pump electrode APE and one decomposition electrode NOE. The measurement and/or calibration may be carried out during the ongoing operation of the gas sensor by removing the gas component and/or oxygen from one of the chambers, by introducing oxygen in a controlled manner into one of the chambers with the aid of electrochemical pumping processes. The changes caused by the introduced oxygen are measured against an additional electrode and the gas sensor may be measured and/or calibrated using the measured values.

Abstract: A notification appliance enclosure that facilitates convenient attachment and removal of a housing. The enclosure may include a mounting plate having a catch lip and a retaining wedge projecting from a surface thereof. The catch lip and the retaining wedge may be spaced apart to define a retaining pocket therebetween, and the catch lip may have a latch release aperture formed therethrough. A housing may fit over the mounting plate and may have a latch tongue extending from a surface thereof fits within the retaining pocket. A release latch may extend from a surface of latch tongue and may fit within the latch release aperture. The engagement between the release latch and the latch release aperture prevents the housing from being pulled away from the mounting plate. The retaining wedge resists movement of the latch tongue and thereby resists disengagement of the release latch from the latch release aperture.

Abstract: Methods and apparatuses, including computer program products, are described for measuring greenhouse gas. A calibration device receives a first sample of atmospheric gas from a first port exposed to the earth's atmosphere. The calibration device receives a second sample of atmospheric gas from a second port exposed to the earth's atmosphere. The calibration device routes the first sample and the second sample to a measurement device for greenhouse gas analysis. The measurement device determines a characteristic of a greenhouse gas present in at least one of the first sample and the second sample. The measurement device transmits data associated with the determined characteristic of the greenhouse gas to a computing device for determining sinks and sources of the gas.

Abstract: A calibration system is provided that supports a plurality of multi-gas detectors and that includes additional options for delivering additional test gases to the detectors. The system can include a calibration module for calibrating a multi-gas detector with a first gas and a replacement module capable of being coupled to the calibration module. When coupled to the calibration module, the replacement module can support delivering a plurality of test gases, not including the first test gas, to the calibration module.

Abstract: A method for calibrating an exhaust gas sensor arranged in a measurement chamber, includes providing a measurement chamber in or adjacent to an exhaust channel of an internal combustion engine. At the start of a calibration phase, exhaust gas present in the measurement chamber is displaced by a filling of the measurement chamber with calibration gas, and at the end of the calibration phase, exhaust gas diffuses into and/or is introduced into the measurement chamber.

Abstract: Calibration and accuracy check systems for a chemical sniffer, such as a breath alcohol tester, which utilize the dispensing of droplets with determinable concentration of alcohol and/or other liquids in a determinable number either directly to a reaction chamber, or into a carrier gas which can be sampled. The systems generally provide for accurate sample concentration being provided to the breath tester while also providing for a simplified system which can be easier to move, and require less operational complexity, than prior wet or dry calibrating systems.

Abstract: A method for adjusting an oxygen sensor measurement within an exhaust gas feedstream output from an internal combustion engine based on humidity includes monitoring relative humidity of ambient air obtained from a humidity sensor. Specific humidity at the oxygen sensor is modeled based on the relative humidity. The oxygen sensor measurement is adjusted based on the modeled specific humidity at the oxygen sensor.

Abstract: A gas regulating device for use in calibration of a gas analyzer has an inlet and an outlet, a valve arrangement comprising at least one valve, and valve regulator for regulating the at least one valve. The gas regulating device is intended to be connected between a calibration gas supply and a gas analyzer that is to be calibrated and the valve regulator is configured to regulate the at least one valve such that gas is allowed to flow through a gas flow path between the inlet and outlet only when a gas pressure in the gas flow path, between the at least one valve and the outlet, falls below a predetermined threshold value. The gas regulating device is used when calibrating side-stream gas analyzers in which case it reduces calibration gas consumption, prevents discharge of calibration gas into the ambient environment and prevents leakages jeopardizing correct calibration.

Abstract: Provided is a device for performing degradation diagnosis of a downstream-side exhaust gas sensor. When a diagnosis condition is met, an intake-air quantity is successively accumulated to obtain an intake-air-quantity accumulation value, an intake-air-quantity average value is obtained as an average of the intake-air quantity from the start of diagnosis, and, on the basis of this intake-air-quantity average value, an intake-air-quantity accumulation threshold value is set. When the intake-air-quantity accumulation value reaches the intake-air-quantity accumulation threshold value, the diagnosis is terminated, and an output reversal number of the downstream-side exhaust gas sensor during the diagnosis period is compared with a threshold value to judge whether the sensor is normal or degraded.

Abstract: A hazard detector assembly for attachment to a surface within a protected zone comprises a detector unit and a test stimulus generator unit.

Abstract: A method of monitoring a sensor of an exhaust system is provided. The method includes evaluating humidity of air entering the exhaust system; and monitoring operation of a sensor in the exhaust system based on the humidity.

Abstract: A gas-solution equilibrium device for a liquid sample gas analyzer includes a temperature-controlled, thermally-conductive mandrel, a coil of gas-permeable tubing wrapped around the mandrel, the gas-permeable tubing having an inlet and an outlet, and a housing having an internal space containing the temperature-controlled, thermally-conductive mandrel, the coil of gas-permeable tubing and a volume of gas where the gas-permeable tubing has a predefined linear length and a predefined wall thickness, the combination of which together is capable of equilibrating a liquid passing through the coil at a predefined flow rate with oxygen in the atmosphere to provide a gas calibration solution in real time at the outlet of the tubing for the liquid gas analyzer.

Abstract: A breath alcohol tester calibration station provides a user-friendly system and method for calibrating a breath alcohol tester with a much lower error rate than current systems and methods for calibrating breath alcohol testers. The calibration station includes a data connection to the breath alcohol tester and a fluid connection between the breath alcohol tester and a calibration standard. The calibration station is used to execute calibration processes on the breath alcohol tester using the calibration standard.

Abstract: An assembly for testing of smoke detectors, installed to detect the presence of smoke in ductwork or through a smoke protected opening, and includes a plenum rated hose assembly having a duct end and a smoke end. The hose assembly smoke end is extendable to within the duct and is terminated with a nozzle directable at an inlet tube of a smoke detector associated with the duct, or to the detector protecting a smoke protected opening. A duct mounting plate is adapted to be sealingly installed to cover an aperture formed within the duct and to retain the hose assembly duct end. Smoke is directed into the hose smoke end. The smoke exits the hose through the nozzle and towards the inlet tube of the duct-mounted smoke detector, or towards the detector for a smoke protected opening, for testing of the smoke detector.

Abstract: A method for manufacturing a gas sensor element includes (a) printing a wiring pattern of a conductive paste on a green sheet for an oxygen-ion conductive solid electrolyte; (b) laminating a plurality of green sheets including the green sheet having been subjected to step (a) and integrating the plurality of green sheets; (c) cutting out a plurality of element bodies from the laminated body; (d) baking the element body cut out by step (c); (e) heating the element body having been subjected to step (d), in a reducing atmosphere; (f) driving the element body having been subjected to step (e), in an inspection-purpose gas atmosphere for a predetermined time period; and (g) inspecting electrical characteristics of the element body having been subjected to step (f). The element body having passed the inspection of step (g) is assembled as a sensor element in a gas sensor.