Born from a three-man partnership at Antioch College, YSI Incorporated has been part of Yellow Springs, Ohio, since its founding in 1948. Now a Xylem Analytics brand, it is known for applying sensor technology to help environmental and industrial professionals understand water conditions, with a history that also includes pioneering life-science instruments. Its quality system is registered to ISO 9001, ISO 14001, and ISO 13485.
ISO 9001:2015
ISO 14001:2015
ISO 13485:2016
European RoHS Directive
Compliance program
CE
WEEE
C-Tick
VCCI
IP67
21 CFR Part 11 Compliance
Compliance program
FDA 510(k) Clearance
Entratech Systems LLCStarted by designer and inventor Mike Richardson after water in his boat fuel nearly left him stranded on Lake Erie, Entratech Systems designs and manufactures electronic sensors and control assemblies in Sandusky, Ohio. The company has spent more than 40 years developing custom water-in-fuel and other protection solutions for OEMs, with patented designs and a turnkey operation that takes projects from engineering through U.S. manufacturing. Entratech operates an ISO 9001:2015-certified management system and is certified to ABYC standards.SANDUSKY, OH
Apera Instruments, LLCSince 1991, Apera Instruments has designed and manufactured electrochemical sensors and meters that help users measure water quality, with its specialty extending from pocket testers to laboratory instruments. The company makes key components in-house, particularly its electrodes, and operates an ISO 9001:2015-certified manufacturing facility; its products are used in more than 60 countries. Apera serves everyone from researchers to hobbyist growers, including with instruments tailored to challenging samples such as pure water, viscous liquids, and high-salinity solutions.COLUMBUS, OH
Kuntze InstrumentsKuntze Instruments is a third-generation, family-owned German company founded in Düsseldorf in 1945, with more than 75 years devoted to water-quality engineering. Its sensors are made, calibrated, and tested in-house at a dedicated facility in Hartha, while Kuntze USA provides local support for North American water-treatment operators. The company is known for bringing German-built measurement expertise to demanding water systems.LOWER BURRELL, PA
Sigma Controls IncSigma Controls, Inc. is a Pennsylvania corporation founded in 1985 that manufactures state of the art instrumentation for the measurement and control of pressure, level and flow applications commonly found in water, wastewater and environmental industries.PERKASIE, PA