A respirator 10 that has a harness 14 and a mask body 12 that is joined to the harness 14. The mask body 12 includes a filtering structure 16 that may contain a plurality of layers of nonwoven fibrous material 58, 60, 62. The layers of nonwoven fibrous material 58, 60, 62 have a thickness A and are welded together by at least two parallel weld lines 34', 34" that are spaced at 0.5 to 6 times A. A mask body that uses parallel weld lines may exhibit better resistance to collapse and may be manufactured at faster speeds than similar structures which use single weld lines of comparable width.
