Lab test results show that Pi & Pie Mask has 99.8% or better Bacterial Filtration Efficiency (BFE), and 98.3% or better Particle Filtration Efficiency (PFE). Pi & Pie Mask uses high quality static charged Melt-blown Fabric as the filtering layer.

Here is a short video explaining the physics behind why Melt-blown Fabric is so efficient in blocking virus like COVID-19 and protecting the wearer. (Video credit: minutephysics.)



Here is the complete Test Report from Intertek, an FDA accredited commercial lab.


  • Pi & Pie Mask has been authorized by FDA under an EUA for use as source control by the general public to help prevent the spread of infection or illness during the COVID-19 pandemic.
  • Pi & Pie Mask is authorized only for the duration of the declaration that circumstances exist justifying the authorization of the emergency use of medical devices, including alternative products used as medical devices, during the COVID-19 outbreak, under section 564(b)(1) of the Act, 21 U.S.C. § 360bbb-3(b)(1) unless the authorization is terminated or revoked sooner.
  • Pi & Pie Mask has NOT been FDA 501(k) cleared for being used as a medical device in hospitals, and it is NOT intended for being used in any surgical setting or where significant exposure to liquid, bodily or other hazardous fluids may be expected, in any clinical setting where the infection risk level through inhalation exposure is high, or in high risk aerosol generating procedures.