Index: firmware/App/Services/TxParams.c
===================================================================
diff -u -r5cc57a6d8eb3721811a2d6ace3176b7074c52fe8 -rd6775171de59386445ffdf70d6b32bcdfc1db07e
--- firmware/App/Services/TxParams.c	(.../TxParams.c)	(revision 5cc57a6d8eb3721811a2d6ace3176b7074c52fe8)
+++ firmware/App/Services/TxParams.c	(.../TxParams.c)	(revision d6775171de59386445ffdf70d6b32bcdfc1db07e)
@@ -21,6 +21,7 @@
 #include "BloodFlow.h"
 #include "Buttons.h"
 #include "Messaging.h"
+#include "ModeStandby.h"
 #include "ModeTreatment.h"
 #include "ModePreTreat.h"
 #include "OperationModes.h"
@@ -575,11 +576,11 @@
 
     switch ( txType )
     {
-        case TREATMENT_MODALITY_HDF:
+        case TREATMENT_MODALITY_HDF_ONLINE_FLUID:
             result = FALSE;
             break;
 
-        case TREATMENT_MODALITY_HD:
+        case TREATMENT_MODALITY_HD_SALINE_FLUID:
             result = ( ( ( param == TREATMENT_PARAM_HDF_DILUTION ) || ( param == TREATMENT_PARAM_SUBST_FLUID_VOLUME ) ) ? TRUE : FALSE );
             break;
 
@@ -738,6 +739,7 @@
     F32  hepDR  = stagedParams[ TREATMENT_PARAM_HEPARIN_DELIVERY_RATE ].sFlt;
     F32  hepBV  = stagedParams[ TREATMENT_PARAM_HEPARIN_BOLUS_VOLUME ].sFlt;
     F32  txVol  = hepBV + ( hepDR * ( hepST / (F32)SEC_PER_MIN ) ) + SYRINGE_PUMP_PRIME_VOLUME_ML + SYRINGE_PUMP_FILL_VOLUME_OFFSET_ML;
+    TREATMENT_TYPE_T modality = (TREATMENT_TYPE_T)stagedParams[ TREATMENT_PARAM_TREATMENT_MODALITY ].uInt;
 
     // Variable to validate acid conversion factor consistency
     U32 acidType        = stagedParams[ TREATMENT_PARAM_ACID_CONCENTRATE ].uInt;
@@ -768,6 +770,13 @@
         result = FALSE;
     }
 
+    // Verify Rx entered modality with the treatment initiation modality
+    if ( modality != getModality() )
+    {
+        reasons[ TREATMENT_PARAM_TREATMENT_MODALITY ] = REQUEST_REJECT_REASON_MODALITY_MISMATCH;
+        result = FALSE;
+    }
+
     return result;
 }