Design Goals

1. Turbidimeter costs less than $100 (for a production model),
2. Reads samples with an accuracy of 0.05 NTU in the sample range 0-5 NTU, and 0.2 NTU in the range of 5-20 NTU,
3. Reads samples with an accuracy of 5% in the range 20-1000 NTU,
4. Can be operated manually, or in automated mode for continuous sampling,
5. Transmits data to an Android phone, via USB connection or Bluetooth,
6. Is powered by 2-4 AAA batteries,
7. Can collect samples, automatedly, every 15-minutes for one month without needing new batteries.

Development Blog→

Why Do It

Our hope is that by proliferating low-cost sampling technology like this turbidimeter, engineers, funders, and community technicians will be able to get a clearer picture of the areas they serve, enabling them to make better decisions and respond more quickly to problems as they arise.

Related Resources

http://cuaguaclara.blogspot.com/2012/07/announcing-new-open-data-project.html

http://wash4all.org/wp/open-source-water-quality-testing-turbidity/

EPA Clean Water Act Approved methods
EPA Nephelometry Standards
Explanation of EPA/ISO standards

Repos

Open Turbidimeter Project on Launchpad (this is where all the project info & bug reports live, and the most recent code).

Contributors

Chris Kelley
Alex Krolick
Clayton Grassick
John Feighery
Yoni Saltzman