Air filtering devices may be helmet-mounted or belt-mounted. The air filtering devices include a filtering device shell and a filtering unit. The filtering unit includes a contaminated-air inlet, a filter assembly in fluid communication with the contaminated-air inlet, a blower assembly in fluid communication with the filter assembly via a duct, and containing a filtered-air outlet, and a filtered-air passageway in fluid communication with the blower assembly outlet and leading to breathing headgear. The blower assembly is vibrationally isolated from the filtering device shell by being only attached to the filtering device shell by the duct. The duct includes an elastomeric material.