Waterproofing membranes consist of waterproof plastic, rubber, or coated-fabric materials ... A satisfactory rate is below 4% (most materials are between 1-2%). Also important is the thickness of the ...
The number is inside the triangular recycling mark. 1, 2, 4 or 5 means the plastic is BPA free. They quite often say BPA free on them. A 3 or a 7 means that the plastic may contain BPA.