Our 4'x8'x2" Eco Folding Mats can be installed outdoors. The mats feature a vinyl casing that makes them impervious to the elements. As far as using them as flooring for playgrounds, these mats may not be the most suitable as they don't have a fall height rating. So if you have larger playsets, your kids may not be as protected while at play. If you have a pretty small playset where a child would only fall about a foot or two, these mats could work for that type of play area, but again, these mats are not fall-height tested. If you are looking for fall height rated flooring, we do offer a wide variety of flooring options on our Playground Flooring page.