Studies show that simple cloth masks and masks without filtration technology do not stop viruses or bacteria. Viruses and bacteria are thousands of times smaller than the strands of cotton or synthetic thread in home made cloth or non-filter masks, allowing airborne particles to pass directly though. BMT VirusGuard™ blocks and restrict a wide range of airborne droplets carrying virus and bacteria as well as pollen, allergens, fly ash, agrictulrual, coal dust.