EXFO OTDR 2 - Manual (Page 49)

Preparing Your OTDR for a Test
OTDR 41
Setting Pass/Fail Thresholds
5. Select the boxes corresponding to the thresholds that you want to use,
and enter the desired values in the appropriate fields.
Note: If you no longer want the application to take into account a particular
threshold, simply clear the corresponding check box.
Note: Selecting or clearing a particular thresholds check box will affect all the
available wavelengths, not only the selected one.
The Revert to Factory
Settings button resets
all the values in the
Pass/Fail Thresholds
tab