Water Pasteurization Indicator
Encyclopedia
A water pasteurization indicator (WAPI) is a simple thermometer that indicates when water has reached pasteurization temperature and is safe to drink. It was invented by Fred Barrett and Dale Andreatta.
Pasteurization
destroys all microorganisms that cause diseases from drinking contaminated water and milk. A small polycarbonate
tube contains a wax that melts when water or milk is heated enough to be pasteurized (65 ˚C/149 ˚F). This saves much fuel by eliminating the need to boil water or milk to ensure that the pasteurization temperature has been reached.
Since water pasteurizes at temperatures well below the boiling point of water, WAPIs save time when solar pasteurizing, and save fuel when using traditional fuels.
WAPIs are often used in projects where solar water pasteurization is taught by Solar Cookers International
and other NGOs.
Pasteurization
Pasteurization
Pasteurization is a process of heating a food, usually liquid, to a specific temperature for a definite length of time, and then cooling it immediately. This process slows microbial growth in food...
destroys all microorganisms that cause diseases from drinking contaminated water and milk. A small polycarbonate
Polycarbonate
PolycarbonatePhysical PropertiesDensity 1.20–1.22 g/cm3Abbe number 34.0Refractive index 1.584–1.586FlammabilityV0-V2Limiting oxygen index25–27%Water absorption – Equilibrium0.16–0.35%Water absorption – over 24 hours0.1%...
tube contains a wax that melts when water or milk is heated enough to be pasteurized (65 ˚C/149 ˚F). This saves much fuel by eliminating the need to boil water or milk to ensure that the pasteurization temperature has been reached.
Since water pasteurizes at temperatures well below the boiling point of water, WAPIs save time when solar pasteurizing, and save fuel when using traditional fuels.
WAPIs are often used in projects where solar water pasteurization is taught by Solar Cookers International
Solar Cookers International
Solar Cookers International is a California 501 nonprofit, non-governmental organization that spreads solar cooking awareness and skills worldwide, particularly in areas with plentiful sunshine and diminishing sources of cooking fuel...
and other NGOs.