In some embodiments, data from a vehicle-borne gas leak detection survey are used to generate an aggregate leak indication search area (LISA) indicator for a plurality of leak indications (measurement peaks) characterizing a single leak or localized set of leaks. A clustering algorithm (e.g. Markov, DBScan) may be used to group a set of indications into a cluster characterizing the leak. Leak indications may be pre-filtered for quality control before assignment to a cluster according to a number of parameters including background gas level, inter-peak distance, peak shape, wind speed, wind direction and/or variability, vehicle speed and/or acceleration, and/or a lower detection threshold for leak flow rate.

A gain switched dual comb spectroscopy device for spectroscopically detecting a sample substance, comprising a first slave laser light source configured to generate a first frequency comb having a first comb free spectral range, and a second slave laser light source configured to generate a second frequency comb having a second comb free spectral range which is different from the first comb free spectral range. A master laser light source is configured to inject seed light in to both slave laser light sources therewith to injection lock the generation of both the first and the second frequency combs. A photodetector part is arranged to combine the first and the second frequency combs and to detect a beat signal the spectrum of which comprises a third frequency comb including beat tones produced by interference between the combined first and second frequency combs. The device comprises a sample detection area configured for receiving the sample for detection and for directing at least one of the first and the second frequency comb to the photodetector part via the sample detection area.

A laser absorption spectrometry system for gas measurement is provided. The system includes an integrated cavity output spectroscopy (ICOS) assembly. The assembly includes a gas cell including a cell body defining an optical cavity, one or more tunable diode lasers having one or more nominal wavelengths, and a reflective collimation mirror positioned in an optical path between the one or more tunable diode lasers and the gas cell.

A calibration method includes receiving data characterizing a first pressure broadening coefficient, a second pressure broadening coefficient and a third pressure broadening coefficient of the target gas absorption associated with a first background gas, a second background gas and a third background gas, respectively. The method further includes, determining a molar ratio associated with the second background gas and the third background such that an effective pressure broadening coefficient associated with a target gas mixture including the second background gas and the third background gas mixed at the determined molar ratio is within a predetermined threshold of the first broadening coefficient. The target gas mixture further includes a target gas. The method also includes calibrating a gas analyzer using the target gas mixture to replace the calibration of the target in the first background gas. The calibration is based on absorption of electromagnetic radiation by the target gas in the target gas mixture.

A gas analyser apparatus using laser absorption spectroscopy includes at least two lasers, preferably up to five, six or seven lasers, and a laser housing (6). The at least two lasers are mounted in the laser housing. The laser housing (6) includes a monolithic main body defining an interior space for receiving the lasers and a lid for sealingly closing the main body. The laser housing is arranged within an outer housing of the gas analyser apparatus. This gas analyser can be assembled and adjusted in a quite simple way.

Systems for measuring a concentration of a target species include a first and second tunable diode laser generating laser light at a respective first and second wavelength each corresponding to respective absorption lines of the target species. A first optical fiber is optically coupled to the first tunable diode laser, and does not support a fundamental mode at the second wavelength. A second optical fiber is coupled to the second tunable diode laser and does not support a fundamental mode at the first wavelength. A fiber bundle includes respective distal ends of the first and second optical fibers, which are stripped of their respective coatings and arranged with their claddings adjacent to each other. A pitch head is configured to project respective optical beams from the fiber bundle through a measurement zone. A catch head located across the measurement zone receives the projected beams and directs them to a sensor.

A gas analyzer includes an optical emitter that irradiates measurement light into a measurement region including a measured-gas, a first optical receiver that receives the measurement light passing through the measurement region, a splitting unit between the optical emitter and the measurement region that splits off a portion of the measurement light irradiated from the optical emitter to yield reference light, a reference unit, and an optical component. The reference unit holds a gas containing a measurement target component identical with the measured-gas but at a known concentration and a second optical receiver that receives the reference light passing through the region including the gas. The optical component is disposed between the splitting unit and the region and expands the beam diameter of the reference light to be larger at the second optical receiver than the receiving diameter of the second optical receiver.

Devices, systems, and methods for determining gas characteristics to monitor transformer operation include extracting gas from transformer fluid for analysis.

Devices, systems, and methods for determining gas characteristics to monitor transformer operation include extracting gas from transformer fluid for analysis.

A method for implementation by a laser spectrometer is provided. The method includes first scanning, by a control unit using a first set of laser spectrometer operating parameters, a first wavelength range by adjusting a wavelength of light of a beam emitted by a laser light source and passing through a sample gas. The first wavelength range encompasses a first spectral feature corresponding to a first constituent. The method also includes at least one second scanning, by the control unit using a second set of laser spectrometer operating parameters, a second wavelength range by adjusting the wavelength of light emitted from the laser light source and passing through the sample gas. The second wavelength range has a second spectral feature corresponding to at least one second constituent. The control unit also determines a first concentration of the first constituent and a second concentration of the at least one second constituent.