==Field experiences==
In a study in Cambodia, 87.5% of the households surveyed had BSFs in use. Time in use ranged from six months to eight years, and the percentage of BSFs still in use did not decline over the length of time elapsed between BSF installation and follow up. Water, sanitation, hygiene, and other factors were analyzed for association with continued filter use.
Households who reported receiving training in operation and maintenance and those who used deep wells (more than 10 meters deep) were found to be statistically significantly
associated with continued BSF use. In BSF households, BSF treatment resulted in a 95% reduction of E. coli and an 82% reduction in turbidity of untreated source water. Furthermore, BSF-usage in households resulted in a 47% reduction of diarrheal disease as compared to control households that did not have BSFs.
However, a significant proportion of BSFtreated and stored samples became re-contaminated after filtration suggesting the need for additional training and education about safe storage and recontamination. Despite recontamination during storage, the concentration of E. colias well as turbidity were still lower in BSF treated and stored water than in untreated water.
The BSF is a robust water treatment technology for use in rural Cambodian households, capable of effective removal of indicator bacteria, specifically E. coli, and significant reduction of diarrheal disease. BSF performance is comparable to other recommended household water treatment interventions, such as the ceramic water purifier; however BSFs provide the additional advantage of not being prone to breakage or needing replacement parts.
To read the full study: [http://www.wsp.org/sites/wsp.org/files/publications/WSP_biosand_cambodia.pdf Improving Household Drinking Water Quality: Use of BioSand Filters in Cambodia]. Water and Sanitation Program, May 2010.
==Manuals, videos, and links==