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HWTS Sanitary Inspection Forms

Hello everyone, 

CAWST and University of Surrey are working to develop Household Water Treatment Sanitary Inspection forms that can be used by community representatives, health workers, water inspectors and humanitarian professionals. Your feedback will help us to ensure that these forms reflect your needs and experience. 

Please review the draft sanitary inspection forms for boiling and household slow sand filters. Your review of each form should take approximately 15 minutes.

Let us know if you have any questions. 

Catherine Francis
Senior advisor, marketing and communications, CAWST

Take the biosand filter survey

CAWST needs your input! In 2023, the biosand filter celebrates a very important milestone - 30 years. We invite all biosand filter implementers and/or trainers to participate in a survey to measure the tremendous impact the technology has had – on the WASH sector, and in people’s lives around the world. The survey includes questions about your experience with implementation, distribution, and impact, and how you have applied new knowledge, skills, and innovations. 
All results will be anonymized, so your answers won’t be attributed to you in our reports. The survey should take between 5 and 10 minutes to complete, and it's currently available in English, Spanish, French and Nepali. Please add a comment if you would prefer to take the survey in another language.
Take the survey now
Thanks for your participation!

Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

Are you training biosand filter technicians?

Did you know that you can access all of CAWST's training materials for free? This includes our lesson plans, manuals, factsheets, presentations, agendas and more! You can find the resources for every workshop we deliver, free and online.

If you have a team making and installing filters, download our workshop materials for biosand filter technicians to teach them how. We really like the following video series to help train biosand filter technicians.

Need help tailoring our training to better meet your needs? We can help you, just contact us at or reply to this email.

Are you feeling intimidated about training others? CAWST can support you to do that too. Check out our training calendar for upcoming dates of our workshops on Delivering Effective WASH Training and Creating Effective WASH Training. 

Don't see any dates in your region? Contact us and we can work to set up something in your region - or provide remote support. 

Emilie SanmartinCAWST
Senior Program Manager, Global Services - CAWST

Let the water Flow! (through the sand)

Installing a biosand filter is one of the most exciting parts of implementation! You get to see all your hard work come together and test your final product.

We have two videos to share with you on how to properly install biosand filters:

What was your flow rate? Did you get it exactly right? Or do you need some help to figure out how to get it right? We are here to help!