this eBook is full of insight into UV treatment of municipal wastewater. You will find answers to many frequently asked questions, including: Why does wastewater need to be treated? What is ...
Tints don't reflect how well the lenses block UV (ultraviolet ... by blocking blue light. They have a reputation for soothing the eyes, and they may be more comfortable for longer wear times. A red ...
Out in the backcountry, a clogged filter could mean the difference between a bout of Giardia and getting to finish your hike. To help you choose the right water treatment option for your purposes, I ...