Design Goals
- Turbidimeter costs less than $100 (for a production model),
- 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,
- Reads samples with an accuracy of 5% in the range 20-1000 NTU,
- Can be operated manually, or in automated mode for continuous sampling,
- Transmits data to an Android phone, via USB connection or Bluetooth,
- Is powered by 2-4 AAA batteries,
- 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