The Escapist Tarp is made of 15 Denier nylon. It is polyurethane coated on the inside and siliconized on the outside. Many siliconized fabrics (including the UltraSil Nano fabric) have a small amount of PFCs along with the siliconization in the DWR finish.
The Escapist Tarp does not have a flame retardent chemical treatment - flame retardents are only required (in North America) for enclosed structures like tents.
In normal use, an Escapist should not need to be washed very often - wiping off dust with a damp sponge should be sufficient. An exception to this might be dust in a burn scar area, which may have a significant soot component. This may need to be washed off: hand washing the Escapist in a large tub with warm water and a small amount of dish soap should take care of soot deposits. Make sure to rinse the Escapist thoroughly after washing, then air dry.
For longer term storage, do not store the Escapist in its stuff sack. Any moisture present on the tarp will remain trapped in the fabric if it is tightly rolled or stuffed - this may compromise the polyurethane coating. The ideal storage place is dry and well ventilated (not a sealed container) - fold the tarp loosely to maximize exposure to ventilating air.