{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T03:09:25Z","timestamp":1773716965792,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2014,4,22]],"date-time":"2014-04-22T00:00:00Z","timestamp":1398124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Turbidity is an internationally recognized criterion for assessing drinking water quality, because the colloidal particles in turbid water may harbor pathogens, chemically reduce oxidizing disinfectants, and hinder attempts to disinfect water with ultraviolet radiation. A turbidimeter is an electronic\/optical instrument that assesses turbidity by measuring the scattering of light passing through a water sample containing such colloidal particles. Commercial turbidimeters cost hundreds or thousands of dollars, putting  them beyond the reach of low-resource communities around the world. An affordable open-source turbidimeter based on a single light-to-frequency sensor was designed and constructed, and evaluated against a portable commercial turbidimeter. The final product, which builds on extensive published research, is intended to catalyze further developments in affordable water and sanitation monitoring.<\/jats:p>","DOI":"10.3390\/s140407142","type":"journal-article","created":{"date-parts":[[2014,4,22]],"date-time":"2014-04-22T12:18:37Z","timestamp":1398169117000},"page":"7142-7155","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":87,"title":["An Affordable Open-Source Turbidimeter"],"prefix":"10.3390","volume":"14","author":[{"given":"Christopher","family":"Kelley","sequence":"first","affiliation":[{"name":"Department of Geography and Environmental Engineering, Johns Hopkins University, 3400 N. Charles St, Ames 313, Baltimore, MD 21218, USA"}]},{"given":"Alexander","family":"Krolick","sequence":"additional","affiliation":[{"name":"Sibley School of Mechanical and Aerospace Engineering, Cornell University, 108 Upson Hall, Ithaca, NY 14853, USA"}]},{"given":"Logan","family":"Brunner","sequence":"additional","affiliation":[{"name":"Department of Geography and Environmental Engineering, Johns Hopkins University, 3400 N. Charles St, Ames 313, Baltimore, MD 21218, USA"}]},{"given":"Alison","family":"Burklund","sequence":"additional","affiliation":[{"name":"Department of Geography and Environmental Engineering, Johns Hopkins University, 3400 N. Charles St, Ames 313, Baltimore, MD 21218, USA"}]},{"given":"Daniel","family":"Kahn","sequence":"additional","affiliation":[{"name":"Department of Geography and Environmental Engineering, Johns Hopkins University, 3400 N. Charles St, Ames 313, Baltimore, MD 21218, USA"}]},{"given":"William","family":"Ball","sequence":"additional","affiliation":[{"name":"Department of Geography and Environmental Engineering, Johns Hopkins University, 3400 N. Charles St, Ames 313, Baltimore, MD 21218, USA"}]},{"given":"Monroe","family":"Weber-Shirk","sequence":"additional","affiliation":[{"name":"School of Civil and Environmental Engineering, Cornell University, 220 Hollister Hall,  Ithaca, NY 14853, USA"}]}],"member":"1968","published-online":{"date-parts":[[2014,4,22]]},"reference":[{"key":"ref_1","unstructured":"American Public Health Association and American Water Works Association (1995). Standard Methods for the Examination of Water and Wastewater, American Public Health Association. [9th ed.]."},{"key":"ref_2","unstructured":"Letterman, R.D. (1999). Water Quality and Treatment: A Handbook of Community Water Supplies, American Water Works Association. 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