Index: firmware/App/Modes/ModeTreatmentParams.c
===================================================================
diff -u -r0aba18162f271555453e7f9266f990a7c22779a6 -rad76efb3e9196e5cee4d8ab824dcd88507c66ade
--- firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision 0aba18162f271555453e7f9266f990a7c22779a6)
+++ firmware/App/Modes/ModeTreatmentParams.c	(.../ModeTreatmentParams.c)	(revision ad76efb3e9196e5cee4d8ab824dcd88507c66ade)
@@ -642,8 +642,14 @@
                 break;
 
             case TREATMENT_PARAM_HEPARIN_PRE_STOP_TIME:
-                result = ( ( value.uInt >= hdInstitutionalRecord.minStopHeparinDispBeforeTxEndMIN ) &&
-                           ( value.uInt <= hdInstitutionalRecord.maxStopHeparinDispBeforeTxEndMIN ) ? TRUE : FALSE );
+                result  = ( ( value.uInt >= hdInstitutionalRecord.minStopHeparinDispBeforeTxEndMIN ) &&
+                            ( value.uInt <= hdInstitutionalRecord.maxStopHeparinDispBeforeTxEndMIN ) ? TRUE : FALSE );
+                // The value of the heparin pre stop time should only be checked if the heparin dispense rate in not zero.
+                // If the stop time is outside of range but the heparin dispense rate is 0, this item has passed regardless.
+                // If the stop time is outside of range and the heparin is not 0, then this item has failed.
+                // Staged params is directly used because the heparin dispense rate is check after the stop so we need to know about it
+                // prior to checking later in this switch case
+                result |= ( stagedParams[ TREATMENT_PARAM_HEPARIN_DISPENSE_RATE ].sFlt <= NEARLY_ZERO ? TRUE : FALSE );
                 break;
 
             case TREATMENT_PARAM_SALINE_BOLUS_VOLUME:
@@ -673,19 +679,19 @@
 
             case TREATMENT_PARAM_UF_VOLUME:
                 result  = ( ( value.sFlt >= hdInstitutionalRecord.minUFVolumeL ) && ( value.sFlt <= hdInstitutionalRecord.maxUFVolumeL ) ? TRUE : FALSE );
-                result |= ( value.sFlt <= NEARLY_ZERO ? TRUE : FALSE ); // There might be a minimum UF volume set in the instit record but a treatment with 0 vol should be allowed
+                result |= ( value.sFlt <= NEARLY_ZERO ? TRUE : FALSE ); // There might be a minimum UF volume set in the institutional record but a treatment with 0 vol should be allowed
                 break;
 
             case TREATMENT_PARAM_HEPARIN_DISPENSE_RATE:
                 result  = ( ( value.sFlt >= hdInstitutionalRecord.minHeparinDispRateMLPM ) &&
                             ( value.sFlt <= hdInstitutionalRecord.maxHeparinDispRateMLPM ) ? TRUE : FALSE );
-                result |= ( 0 == value.sFlt ? TRUE : FALSE ); // Even if the minimum is not 0, 0 is accepted meaning heparin can be turned off
+                result |= ( value.sFlt <= NEARLY_ZERO ? TRUE : FALSE ); // Even if the minimum is not 0, 0 is accepted meaning heparin can be turned off
                 break;
 
             case TREATMENT_PARAM_HEPARIN_BOLUS_VOLUME:
                 result  = ( ( value.sFlt >= hdInstitutionalRecord.minHeparinBolusVolumeML ) &&
                             ( value.sFlt <= hdInstitutionalRecord.maxHeparinBolusVolumeML ) ? TRUE : FALSE );
-                result |= ( 0 == value.sFlt ? TRUE : FALSE ); // Even if the minimum is not 0, 0 is accepted meaning heparin can be turned off
+                result |= ( value.sFlt <= NEARLY_ZERO ? TRUE : FALSE ); // Even if the minimum is not 0, 0 is accepted meaning heparin can be turned off
                 break;
 
             default: