MTS Model 286-31 Transient Permeability Pore Pressure Intensifier - Manual (Page 65)

Running a Transient Permeability Flow Test
286.31 Transient Permeability Pore Pressure Intensifier Operation 65
4. Purge and fill the upper pore pressure line.
Turn the Reservoir Return and Pore Fluid Output valves to the Open
position.
Go on to step 5 as soon as bubble–free fluid comes out of the upper pore
pressure line.