Emerald N95 Disposable Respirator Face Mask 20 per box - One Size Fits Most Approved by NIOSH (National Institute for Occupational Safety and Health), these single-use N95 masks guard against microorganisms, body fluids, and particulate material. Emeralds N95 masks are easy to put on and take off, and contain no fiberglass. Thanks to a close facial fit and highly effective filtration system, the protective capabilities of N95 respirator masks often surpass those of regular face masks.N95 masks are intended to be used for protection against solids, such as those from minerals, coal, iron ore, flour and many other substances. They are extremely durable with a soft and comfortable inner surface ; they also have an adjustable nosepiece and secured headstraps to provide proper fit. These masks have a 510(K) number for the medical market and can be used in TB situations as recommended by OSHA.