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How to use uv to sanitize water
Purchase a portable uv water purifier.
Portable uv water purifiers can be found online or at your local outdoor store. There are a few different models to choose from depending on what you are looking for.
Things to consider are the amount of water you need to sterilize and the weight of the device. You may be able to find a small uv pen that sterilizes water, such as the steripen.