Abstract: A plastic bag comprising a first face and a second face, at least a portion of each being 2-ply and having an intermediate space therebetween, the 2-ply portion of the first face having an inner layer of air-impervious plastic material having openings therein; the 2-ply portion of the second face having an outer layer of air-impervious plastic material, the outer layer having openings therein permitting air to pass therethrough, the openings of the outer layer having a smaller average opening area than an average opening area of the openings of the inner layer of the first face; and a filtering chamber formed between the inner layer and the outer layer such that air in an interior of the bag may egress the bag by passing through the filtering chamber, the air being at least partially filtered of particulate matter as it egresses the bag.