{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T19:14:41Z","timestamp":1791486881696,"version":"4.3.4"},"reference-count":51,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,3,26]],"date-time":"2020-03-26T00:00:00Z","timestamp":1585180800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A quantum cascade laser-based sensor for ambient air monitoring is presented and five gases, affecting the air quality, can be quantified. The light sources are selected to measure CO, NO, NO2, N2O and SO2. The footprint of the measurement setup is designed to fit in two standard 19\u201d rack (48 cm \u00d7 65 cm) with 4 height units (18 cm) whereas one is holding the optical components and the other one contains the electronics and data processing unit. The concentrations of the individual analytes are measured using 2f-Wavelength Modulation Spectroscopy (2f-WMS) and a commercially available multipass gas cell defines the optical path. In addition, CO can also be measured with a dispersion-based technique, which allows one to cover a wider concentration range than 2f-WMS. The performance of this prototype has been evaluated in the lab and detection limits in the range of 1ppbv have been achieved. Finally, the applicability of this prototype for ambient air monitoring is shown in a five-week measurement campaign in cooperation with the Municipal Department for Environmental Protection (MA 22) of Vienna, Austria.<\/jats:p>","DOI":"10.3390\/s20071850","type":"journal-article","created":{"date-parts":[[2020,4,1]],"date-time":"2020-04-01T03:44:13Z","timestamp":1585712653000},"page":"1850","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":45,"title":["A Quantum Cascade Laser-Based Multi-Gas Sensor for Ambient Air Monitoring"],"prefix":"10.3390","volume":"20","author":[{"given":"Andreas","family":"Genner","sequence":"first","affiliation":[{"name":"Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9\/164, 1060 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro","family":"Mart\u00edn-Mateos","sequence":"additional","affiliation":[{"name":"Electronics Technology Department, Universidad Carlos III de Madrid, C\/Butarque 15, 28911 Legan\u00e9s, Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6503-854X","authenticated-orcid":false,"given":"Harald","family":"Moser","sequence":"additional","affiliation":[{"name":"Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9\/164, 1060 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhard","family":"Lendl","sequence":"additional","affiliation":[{"name":"Institute of Chemical Technologies and Analytics, TU Wien, Getreidemarkt 9\/164, 1060 Vienna, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.5194\/acp-17-1775-2017","article-title":"Cleaning up the Air: Effectiveness of Air Quality Policy for SO2 and NOx Emissions in China","volume":"17","author":"Mijling","year":"2017","journal-title":"Atmos. 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