What is Delta P?
The Differential Pressure (DP) is a test that measures how easily air is passed from one side of the mask to the other. This indicates how easily the wearer can breathe through the mask, and is in indicated by Delta P. Higher DP indicates air is more difficult to push through. This could result in a “blow-by” effect (escape of air, and contamination from the sides of an improperly work mask), or even incorrect use by the wearer. While not as comfortable, the higher Delta P results in better filtration.
The goal of a face mask manufacturer is to provide multiple SKU options that give the operator the choice of an appropriate balance between effective filtration and operator comfort, per standard operating procedures (SOPs).