Welcome to Eco Sensors Division of KWJ Engineering Inc.

Eco Sensors Division of KWJ Engineering Inc. is the premier designer and supplier worldwide of low-cost ozone sensing instruments. These are used to monitor safety in the workplace, control ozone generators, monitor and control processes such as food production and storage, deodorization, sterilization, and measuring ozone dissolved in water. Our instruments are simple, user-friendly and inexpensive. We have also always designed and manufactured VOC (volatile organic compounds) instruments which continue to enjoy market acceptance. We have grown every year since our incorporation in 1991 and have been consistently profitable.

The majority of Eco Sensors’ sales are through distributors and OEMs, so we don’t know who or exactly how many end-user customers we have. We estimate that we have over 30,000 customers spread over North America, Europe and the Pacific Rim. Half our sales are export. Eco Sensors’ products are sold by many specialty istributors and by ozone generator manufacturers and systems integrators.

Ozone Sensors

Eco Sensors Division of KWJ Engineering Inc. has been in this application for ten years, but through unique designs has many satisfied in diverse applications include monitoring ozone in air and dissolved in water at:


  1. Water treatment plants
  2. Water bottling plant
  3. Ultra pure water plants
  4. Aquariums
  5. Air treatment for offices, conference rooms, casinos
  6. Laundries for healthcare facilities and hotels
  7. Fruit, vegetable and meat storage
  8. Semiconductor manufacturing
  9. Cooling towers
  10. Electric power plants
VOC Sensors

This is Eco Sensors’ original business, starting in 1992. There are many hundreds of customers. Almost are small businesses grouped into these applications:

  • Dry cleaners
  • Woodworking shops
  • Printers
  • Hospital sterilization
  • Chemical operations
  • Hazmat projects
  • Fumigations services
  • Filter verification
Design, Testing, Service and Manufacturing

All manufacturing is done in the USA. Most of our manufacturing is done in an ISO-9000 plant with electronics manufacturing done to IPC-610. As soon as possible, we have our products tested for CE conformity. Our ozone calibration lab has its analyzers calibrated traceable to NIST. We are dedicated to the customer, seeking always to provide the customer with the highest value. We never stop making improvements, minor and major, to keep our products state of the art.

Eco Sensors® News and Events

March, 2005 We showed at Ozone IV (ozone for the Food and Agriculture industries) in Fresno, California. The conference was very well attended, and everyone agreed that ozone for food treatment and storage is the fastest growing ozone application. Our OS-4 designed specifically for food storage, was enthusiastically received by everyone in this market.

August, 2005 We showed at the International Ozone Association (IOA) World Congress in Strasbourg, France. The congress and exhibition was a great success. Among the areas of interest were food treatment, medical applications, and waste water cleanup.

September, 2006 We showed at the IOA Pan American Meeting in Arlington, Texas where we introduced our new model A-22 versatile portable monitor.

August, 2007 We had a succesful showing at the IOA-IUVA World Congress for ozone and UV in Los Angeles, California. For information about the International Ozone Association (IOA) and upcoming meetings, visit www.io3a.org.

January, 2008 We were acquired by KWJ Engineering Inc., Newark, California. All operations except service have been moved to California to benefit by more facilities and personnel.

August, 2008 We had a very successful booth at the IOA ozone meeting in Orlando, Florida. Our new miniature DO3 and PO3 “pocket” ozone sensors were the hit of the show.

September, 2010 We showed at the IOA Pan American Meeting in Seattle, Washington. Larry Kilham gave a keynote speech on creativity and innovation in the ozone industry, and Joe Stetter presented a paper on improvements in multi-sensor ozone instruments.

Our founder has written a book, MegaMinds: How to Create and Invent in the Age of Google, that describes his successful approaches to product development including for the Eco Sensors Division of KWJ Engineering Inc. For more information about the invention process and the book, click here.

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