al zain civil disposable masks and 3 ply surgical mask

Performance of surgical masks is evaluated based on such parameters as filtration (mask capture of exhaled aerosols), exposure (transfer of aerosols from outside), mask airflow resistance (pressure difference during breathing, ?P, also known as breathability), liquid penetration resistance, air and water vapor permeability, water repellency (for outer and inner surfaces).

Filtration and exposure is typically measured in bacterial filtration efficiency (BFE) using particles of size 3.0 ?m. Particulate filtration efficiency (PFE) using particles of size 0.3 ?m is only measured in China.