SODIS stands for Solar Disinfection. It’s a simple method of making safe drinking water by using the UV radiation of the sun. UV light penetrates through clear plastic or glass bottles and kills pathogenic bacteria and organisms by damaging their protein structures. Usually 6 or 8 hours of direct sunlight on a clear day is adequate to kill most pathogens. UV radiation is stronger in southern latitudes and at higher elevations. Heat also helps with the process by killing organisms such as viruses that are more resistant to UV radiation. Small bottles work best and the water should be clear, not cloudy.