Index: firmware/App/Services/TxParams.h
===================================================================
diff -u -r83310420ae862de4724f8cfbbaeda9936c47801b -r52787cd53986cfd0abb7e674bf096898e5070f9a
--- firmware/App/Services/TxParams.h	(.../TxParams.h)	(revision 83310420ae862de4724f8cfbbaeda9936c47801b)
+++ firmware/App/Services/TxParams.h	(.../TxParams.h)	(revision 52787cd53986cfd0abb7e674bf096898e5070f9a)
@@ -37,6 +37,8 @@
 #define MAX_UF_RATE_ML_MIN                      ( 2000.01F / (F32)MIN_PER_HOUR )            ///< Maximum ultrafiltration rate (in mL/min).  Added small decimal to prevent float round off issues.
 #define MIN_UF_RATE_ML_MIN                      ( 0.0F )                                    ///< Minimum ultrafiltration rate (in mL/min).
 #define MAX_UF_VOLUME_ML                        ( 8 * ML_PER_LITER )                        ///< Maximum ultrafiltration volume (in mL).
+#define MIN_ISOLATED_UF_DURATION_MIN            ( 30 )                                      ///< Minimum isolated UF session duration (in min).
+#define MIN_ISOLATED_UF_VOLUME_ML               ( 0.1F * (F32)ML_PER_LITER )                ///< Minimum isolated UF volume (in mL).
 
 /// Record structure for a treatment parameters payload from UI.
 typedef struct
@@ -104,17 +106,54 @@
     F32 uFVolume_L;                                         ///< Current ultrafiltration volume (in L).
 } CURRENT_TREATMENT_PARAMS_DATA_PAYLOAD_T;
 
-/// Payload record structure for treatment parameter range broadcast messages.
+#pragma pack(push, 1)
+
+/// Payload record structure for requesting an isolated UF duration change.
 typedef struct
 {
-    U32 minTreatmentTime;                                               ///< Minimum treatment duration (in minutes)
-    U32 maxTreatmentTime;                                               ///< Maximum treatment duration (in minutes)
-    F32 minUFVolume;                                                    ///< Minimum ultrafiltration volume (in mL)
-    F32 maxUFVolume;                                                    ///< Maximum ultrafiltration volume (in mL)
-    U32 minDialRate;                                                    ///< Minimum dialysate flow rate (in mL/min)
-    U32 maxDialRate;                                                    ///< Maximum dialysate flow rate (in mL/min)
-} TREATMENT_PARAM_RANGE_BROADCAST_PAYLOAD_T;
+    U32 mDuration;                                              ///< Requested isolated UF duration in minutes.
+} ISOLATED_UF_DURATION_CHANGE_REQUEST_PAYLOAD_T;
 
+/// Payload record structure for requesting an isolated UF volume goal change.
+typedef struct
+{
+    U32 mDuration;                                              ///< Requested isolated UF duration in minutes.
+    U32 mVolume;                                                ///< Requested isolated UF volume goal in mL.
+} ISOLATED_UF_VOLUME_GOAL_CHANGE_REQUEST_PAYLOAD_T;
+
+/// Payload record structure for confirming an isolated UF settings change.
+typedef struct
+{
+    U32 mConfirmed;                                             ///< TRUE if user confirms the staged isolated UF settings.
+} ISOLATED_UF_CONFIRM_REQUEST_PAYLOAD_T;
+
+/// Payload record structure for isolated UF duration change responses.
+typedef struct
+{
+    U32 mAccepted;                                              ///< Accepted/Rejected.
+    U32 mReason;                                                ///< Rejection reason if not accepted.
+    U32 mVolumeMax;                                             ///< Maximum isolated UF volume in mL for the requested duration.
+} ISOLATED_UF_DURATION_CHANGE_RESPONSE_PAYLOAD_T;
+
+/// Payload record structure for isolated UF volume goal change responses.
+typedef struct
+{
+    U32 mAccepted;                                              ///< Accepted/Rejected.
+    U32 mReason;                                                ///< Rejection reason if not accepted.
+    U32 mVolume;                                                ///< Isolated UF volume goal in mL.
+    U32 mDuration;                                              ///< Isolated UF duration in minutes.
+    U32 mRate;                                                  ///< Isolated UF rate in mL/min.
+} ISOLATED_UF_VOLUME_GOAL_CHANGE_RESPONSE_PAYLOAD_T;
+
+/// Payload record structure for isolated UF confirmation responses.
+typedef struct
+{
+    U32 mAccepted;                                              ///< Accepted/Rejected.
+    U32 mReason;                                                ///< Rejection reason if not accepted.
+} ISOLATED_UF_CONFIRM_RESPONSE_PAYLOAD_T;
+
+#pragma pack(pop)
+
 /// Payload record structure for treatment duration validate request.
 typedef struct
 {
@@ -256,6 +295,11 @@
 F32  getTreatmentParameterF32( TREATMENT_PARAM_T param );                           // Get a specified floating point treatment parameter
 
 BOOL validateAndSetTreatmentParameters( MESSAGE_T *message );                       // User provided treatment params to be set and validated
+//BOOL validateAndSetUFVolume( MESSAGE_T *message );                                // User provided ultrafiltration volume to be set and validated
+F32  calculateIsolatedUFRateMlMin( U32 durationMin, F32 volumeGoalMl );             // Calculate isolated UF rate (mL/min) from duration and volume goal
+BOOL handleIsolatedUFDurationChangeRequest( MESSAGE_T *message );                   // User requested isolated UF duration change
+BOOL handleIsolatedUFVolumeGoalChangeRequest( MESSAGE_T *message );                 // User requested isolated UF volume goal change
+BOOL handleIsolatedUFConfirmRequest( MESSAGE_T *message );                          // User confirmed/rejected isolated UF settings change
 
 // Edit Treatment parameter handlers
 BOOL validateAndSetTreatmentDuration( MESSAGE_T *message );                         // User provided treatment duration to be set and validated