Index: firmware/App/Modes/SelfTests.c
===================================================================
diff -u -r94dab74a6432263dc4569e0cf8f9fa0b01bf1917 -r86ccf9565595418e7424e5cd26b5abdd63482f04
--- firmware/App/Modes/SelfTests.c	(.../SelfTests.c)	(revision 94dab74a6432263dc4569e0cf8f9fa0b01bf1917)
+++ firmware/App/Modes/SelfTests.c	(.../SelfTests.c)	(revision 86ccf9565595418e7424e5cd26b5abdd63482f04)
@@ -51,8 +51,8 @@
 #define ARTERIAL_PRESSURE_SELF_TEST_LOW_LIMIT_MMHG          -50.0F                                  ///< Arterial pressure low limit after running blood pump.
 #define VENOUS_PRESSURE_SELF_TEST_HIGH_LIMIT_MMHG           400                                     ///< Venous pressure high limit after running blood pump.
 
-#define DECAY_PRESSURE_DIFF_TOLERANCE_MMHG                  5.0F                                   ///< Difference in pressure readings after the pump stops (in mmHg).
-#define STABILITY_PRESSURE_DIFF_TOLERANCE_MMHG              2.0F                                   ///< Difference in pressure readings while in a stable pressured state (in mmHg).
+#define DECAY_PRESSURE_DIFF_TOLERANCE_MMHG                  5.0F                                    ///< Difference in pressure readings after the pump stops (in mmHg).
+#define STABILITY_PRESSURE_DIFF_TOLERANCE_MMHG              2.0F                                    ///< Difference in pressure readings while in a stable pressured state (in mmHg).
 #define NORMAL_PRESSURE_DIFF_TOLERANCE_MMHG                 10.0F                                   ///< Difference in pressure readings after return to normal state tolerance (in mmHg).
 
 #define DIP_FLOW_RATE_SETUP_ML_MIN                          150                                     ///< Dialysate inlet pump flow rate during the setup for wet self-test.
@@ -1034,6 +1034,18 @@
     F32 arterialDecayDiff = 0;
     F32 venousDecayDiff =  0;
 
+    // update peak pressure value from pressurized state
+    // if pressure continues to increase due to filter lag
+    if (arterialPressure > peakArterialPressure )
+    {
+        peakArterialPressure = arterialPressure;
+    }
+
+    if ( venousPressure > peakVenousPressure )
+    {
+        peakVenousPressure = venousPressure;
+    }
+
     if ( ( TRUE == didTimeout( pressureSelfTestDecayStartTime, DECAY_PRESSURE_SELF_TEST_TIME ) ) )
     {
         arterialDecayDiff = fabs( arterialPressure - peakArterialPressure );
@@ -1052,7 +1064,6 @@
         }
     }
 
-
     if ( TRUE == doesAlarmStatusIndicateStop() )
     {
         state = DRY_SELF_TESTS_STOPPED_STATE;