The present invention relates to a multilayer protective enclosure for protecting humans, animals or perishables from hazardous agents in the environment. The enclosure contains a porous adaptive membrane structure that has movable membranes with insertable protrusions. The structure can be made to change its gas, liquid or particulate permeability in response to surrounding environmental conditions. Hence, the enclosure is highly breathable in a non-hazardous environment but impermeable or only semipermeable in a hazardous environment.