How to capture tiny particles with HEPA filters
HEPA filters are made up of a mat-like material with fibers. The fibers must be arranged precisely so that particles stick to the fibers in one of three ways
1. Interception: this is the first line of defense, where most particles in the air flow stream naturally adhere to the fibers.
2. Impaction: this is the second line of defense, where the particles that are too large for interception are trapped in the curved contours of the fibers.
3. Diffusion: this is the final defense, which traps molecules that are too small for either interception or impaction by forcing them to collide with gas molecules.
One of the earliest uses of HEPA filters in vacuums was for asbestos removal. HEPA filters have also been used in lead paint abatement projects. Most recently, HEPA vacuums have been used in various industries to protect the health and safety of workers and residents.
