What are the four principles of air filtration?

The four principles of air filtration focus on the mechanisms that enable particles and contaminants to be removed from the air stream effectively. The principles of impingement, interception, diffusion, and straining describe how particles interact with filter media, leading to their capture.

Impingement occurs when particles collide with filter fibers, causing them to be trapped. Interception refers to the process where particles follow the airstream but come into contact with and stick to fibers due to their size. Diffusion relates to the random motion of smaller particles, which can lead them to collide with fibers and be captured more effectively. Straining involves the physical removal of particles larger than the gaps in the filter material, effectively blocking them from passing through.

Together, these principles form the foundation of how filters operate across various applications, making this understanding crucial for designing and selecting effective air filtration systems.