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Assume you like https://www.airvisual.com/earth or https://www.airvisual.com/air-quality-map but your city/country is not yet on the map. Or you already have Node but missing outdoor air quality measurements. There is a way to fix it. You can install and register your AirVisual node outdoor. Yes, it needs yet another node to be bought. Article on AirVisual site about sharing your data : http://support.airvisual.com/knowledgebase/articles/948895-how-can-i-make-my-outdoor-node-pro-s-data-public
And below is example of
DIY case for outdoor installation of AirVisual Node
AirVisual node itself is absolutely indoor device. It needs good weather proof case that is also have good airflow.
Wrong way
It just a test. Not a case really. Not an outdoor. 
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So, let's measure and buy something that might be used as an outdoor case.
Creating an outdoor case
Do It Yourself outdoor case for AirVisual Node using plastic air vent grilles and plastic flower pots. Some cuts and glue
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Those outdoor installation was succesfully registered and used for 1.5 years.
Some minor improvements after 1.5 years
Strong magnet mount, new wire and USB socket on the case. Old USB extention cable was still working, but looks oxidized. So to ensure operation for some couple of more years..
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