It's a logo of a rectangle in portrait orientation with curved edges. Coming through the rectangle from left to right are curved line waves. There are three of them and they curve down then up then down.
This is the Air Quality icon for Windows 10
. Here we go. Optimized for 32x32 px, these are the simplest icons in the line style. Downloadable formats are PNG and SVG, among others. Icons8 icon pack is unique in providing a huge number of icons designed by the same team of four designers who create the new icons every working day in the same style and with the same quality. Same cool as the Bat Face, huh.