On The Ground - SOUTH FLORIDA USA Available for Immediate Delivery FDA, CDC, NIOSH CERTIFIED The ZYB-13 particulate respirator mask is a NIOSH Certified disposable N95 mask that offers at least 95% filtration rate of airborne particles. The N95 designation means that when subjected to careful testing, the respirator blocks at least 95 percent of very small (0.3 micron) test particles. The ZYB-13 particulate respirator mask is a NIOSH Certified disposable N95 mask that offers at least 95% filtration rate of airborne particles (NIOSH Approval Number: 84A-7877). The N95 designation means that when subjected to careful testing, the respirator blocks at least 95 percent of very small (0.3 micron) test particles. This mask was also specifically designed to maximize protection while improving comfort through an adjustable nose clip. It also allows for easy breathing and speaking without comprising filtration effectiveness.