User and partner feedback is methodically collected throughout all SaWa Projects and National Programs. The high scores, multiple endorsements, and strong partnerships with governments and NGOs underline the need for SaWa’s efficacy in providing safe drinking water to people in low-income communities.
“SaWa Bag is especially good as it provides a closed loop solution that enables water purification for the individual family, while providing safe storage, and easy dispensing, ensuring no recontamination and only safe water.
– Godfrey Peterson Baguma UNHCR WASH Officer, Kyangwali Refugee Settleme
SaWa Bag’s purification technology is based on PET bottles’ 40-year-old Solar Water Disinfection (SODIS) process, which the World Health Organization (WHO) has endorsed as a safe way to purify water. It works by harnessing UVA and UVB rays and heat from the sun.
Combining these three processes kills the organic pathogens of concern in water. Specifically, the UVA forms reactive oxygen species (ROS) in the water, which is critical in inactivating microorganisms. UVB directly damages the organism’s DNA and RNA. The heat initiates a heat pasteurization that works with UV processes to accelerate disinfection.
SaWa Bag further improves the purification process by using a specialized plastic foil and construction that significantly increases solar penetration and makes the process faster, killing a more comprehensive range of bacteria, viruses, and protozoa with a performance of 99.9%. The model illustrates the sun emitting the UV rays that reach the bag, which initiates the SaWa product’s purification process.
The graph below illustrates the UV measurements of the SaWa Bag and an ordinary PET water bottle.
The significant difference is the instant onset of increased UVB (lower wavelength) penetration for the SaWa Bag, as this radiation will purify water faster.
SaWa Bag can hold 4 liters of water. Filled with water, the bag forms 3 cavities that ensure a rigid product and optimal solar exposure. It weighs 100g and takes up little space, making it easy to transport. SaWa Bag’s closed eco-system storage prevents the cleaned, safe drinking water from becoming recontaminated.
The water is biologically contaminated.
The water is consumed within 3 days of solar exposure.
The water has a turbidity of less than 30 NTU (if SaWa logo can be seen through the lid with water in it, cleaning can proceed).
The water is exposed to the full recommended consecutive period of sunlight.
The water is not recontaminated by, for example, introducing it to a contaminated container.
SaWa Bag is placed facing the sun with the transparent side up.