A gas analyzer includes: a column that separates a component in a sample gas; a valve that switches, between a test sample gas and a standard sample gas, the sample gas to be supplied to the column; a valve that adjusts an introduction amount of the sample gas to be supplied to the column; a detector that detects, by gas chromatography, the component in the sample gas separated by the column; and a control device. The control device controls the valve to allow the introduction amount to be a predetermined amount, calculates a peak area value of a chromatogram obtained by the detector when the introduction amount is the predetermined amount, and calculates a correspondence between the introduction amount and the peak area value.

A gas sample introduction device includes a sample container connection flow path, a sample loop and a first flow path switching valve, having a first state in which the pressurizing gas is supplied to the sample container connection flow path via the sample loop and a second state in which the pressurizing gas is supplied to the sample container connection flow path without via the sample loop. A leak check method includes a first determination step of determining whether or not there is a gas leak by setting the first flow path switching valve to a first state and a second determination step of identifying a location of a gas leak by performing a second determination of whether or not there is a gas leak by setting the first flow path switching valve to a second state, when there is a gas leak in the first determination step.

A system includes a system housing including an inlet, at least one gas sensor responsive to a first analyte gas other than oxygen within the system housing and in fluid connection with the inlet, and a sensor responsive to oxygen within the system housing and in fluid connection with the inlet. The sensor responsive to oxygen is formed to be chemically separate from the at least one gas sensor responsive to the first analyte gas other than oxygen. The sensor responsive to oxygen is responsive to a change in the concentration of oxygen arising from creation of a driving force in the vicinity of the inlet to provide an indication of a state of a transport path between the inlet of the system and the at least one gas sensor responsive to the first analyte gas other than oxygen.

A method of operating a sensor system including at least one sensor to detect a first gas analyte and a control system includes electronically interrogating the sensor to determine the operational status thereof and, based upon the results of the electronic interrogation, the control system initiating an automated maintenance procedure for the sensor.

A sensor system includes a sensor element to which a control current is inputted, a DA converter to output the control current, and a control part configured to generate a control current instruction value and input the control current instruction value to the DAC, and further includes an instruction value generation part to sequentially generate an inspection current instruction value to be inputted to the DAC instead of the control current instruction value, an inspection current detection part to detect an inspection current value of an inspection current, an expected value calculation part to calculate an inspection current expected value, a difference value acquisition part to acquire a difference value between the inspection current value and the inspection current expected value, and a failure detection part to detect a failure of a bit in the DA converter, by frequency analysis of a temporal change of the difference value.

A gas-detecting apparatus, having a gas inlet and a gas outlet, for detecting a false alarm is disclosed. The gas-detecting apparatus comprises a control module, a sensor module, and an air chamber. In an example embodiment, the sensor module is electrically connected with the control module. The sensor module has a sensor inlet and a sensor outlet. The sensor inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus. The air chamber has an air inlet and an air outlet, wherein the air inlet is fluidly coupled to the gas inlet of the gas-detecting apparatus and the air outlet is fluidly coupled to the gas outlet. The control module is configured to receive a first sensing signal for a first level of gas from the sensor module and determine whether magnitude of the first sensing signal is higher than a first threshold value. In an instance when the magnitude of the first sensing signal is higher than the first threshold value, the control module causes the air chamber to supply ambient air to the sensor module through the sensor inlet of the sensor module.

A gas sample introduction device includes a sample container connection flow path, a sample loop and a first flow path switching valve, having a first state in which the pressurizing gas is supplied to the sample container connection flow path via the sample loop and a second state in which the pressurizing gas is supplied to the sample container connection flow path without via the sample loop. A leak check method includes a first determination step of determining whether or not there is a gas leak by setting the first flow path switching valve to a first state and a second determination step of identifying a location of a gas leak by performing a second determination of whether or not there is a gas leak by setting the first flow path switching valve to a second state, when there is a gas leak in the first determination step.

A method for monitoring environmental data and a monitoring system are provided. The method includes that: a second server receives first environmental data from a first server; the second server determines that data loss occurs in the first environmental data; the second server obtains lost data in the first environmental data from the first server; the second server obtains second environmental data according to the first environmental data and the lost data; and responsive to a concentration of a sampled gas in the second environmental data exceeding a preset concentration threshold, the second server sends warning information to a terminal device.

A method for testing a plurality of sensor devices, a panel and a sensor component are disclosed. In an embodiment a method includes providing the plurality of sensor devices, each sensor device including a sensor element configured to sense an ambient condition, a heating element to heat the sensor element, connection terminals for a supply voltage and at least one connection terminal for a sense signal indicative of a state of the sensor element, providing a panel including a plurality of groups of connection pads, the connection pads of each one of the groups configured to be connected to the connection terminals of one of the sensor devices, mounting the sensor devices to the groups of connection pads, applying a supply voltage to the sensor devices and concurrently heating the heating elements of the sensor devices to an elevated temperature and calibrating the sensor devices at least one after another.

A method for determining a false negative rate of mobile monitoring and requisite number of mobile monitoring vehicles. The method focuses on road network of an urban area, by installing air pollution detection equipment on the mobile monitoring vehicles, to monitor air quality of the urban area. The method includes establishing a curve model of monitoring times for the mobile monitoring vehicles, determining two parameters of expected indicator: covered range, number of scheduled detections; and finding out a requisite number (C.sub.0) of the mobile monitoring vehicles, corresponding to a curve model which meets the two parameters of expected indicator.