NIOSH approved for hydrogen fluoride and certain oil and non-oil based particles. Use with 3M™ Facepieces 6000 Series or 3M™ Facepieces 7000 Series with bayonet filter holders. When properly fitted, use for a variety of applications including aluminum processing for concentrations up to 10 times the Permissible Exposure Limit (PEL) with half facepieces or 50 times PEL with full facepieces. Full facepieces must be quantitatively