Once we know the Average Allowable dartt recorder, we apply it to a test by sampling a short duration of pressure x time data and multiply it out to display it as psi/min, then compare that to the specified Average Allowable ROC. Usually once the BOP/Intervention system has been landed and latched, a final pressure test re-tests all previously tested connections.
To aid in testing, Test Pressure and Hold Period can be combined into a rate of change (ROC). For example, where the Hold Period = 10min and the Allowable Pressure Loss = 30psi, the Average Allowable ROC = 3psi/min. That is, if the average rate of Pressure Chart Recorder change during the 10min Hold Period =< 3psi/min, then the hold and allowable loss component of the test specification will have been achieved.