Bubble point

The pressure at which air will pass through a wetted membrane filter. This pressure is correlated to the pore size of the membrane and thus this test can be used to confirm the pore size and integrity of a membrane or filter device.

FAQ
The pressure at which air will pass through a wetted membrane filter. This pressure is correlated to the pore size of the membrane and thus this test can be used to confirm the pore size and integrity of a membrane or filter device.
Bubble point test technique. A bubble point test is a technique that precedes to measure the needed pressure to apply the upstream side of a filter open pore of causing bulk through a wetted filter’s largest pores.
For thermodynamics, the bubble point can be known as the temperature at a given pressure that first bubbles when the vapour is made when heating a two or more-component liquid. For a singular component, the dew and bubble point are the same, and named the boiling point.
The membrane filter is wetted completely with water (hydrophilic membranes) or isopropanol (hydrophobic membranes) and placed in an inline filter holder. Continuously increasing air pressure is applied to the inlet side until air bubbles appear at the outlet side. The bubble point correlates directly with the pore size and can be used to check the integrity of the filter.