Index: firmware/App/Modes/SampleWater.c
===================================================================
diff -u -rb6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7 -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Modes/SampleWater.c	(.../SampleWater.c)	(revision b6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7)
+++ firmware/App/Modes/SampleWater.c	(.../SampleWater.c)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -15,6 +15,7 @@
 *
 ***************************************************************************/
 
+#include "AlarmMgmt.h"
 #include "DGInterface.h"
 #include "HDDefs.h"
 #include "SampleWater.h"
@@ -134,6 +135,62 @@
 
 /*********************************************************************//**
  * @brief
+ * The signalSampleWaterUserAction function signals a sample water user action
+ * has been requested. The request is handled and responded to.
+ * @details Inputs: none
+ * @details Outputs: action handled, request reponsed to
+ * @param action User action requested
+ * @return none
+ *************************************************************************/
+void signalSampleWaterUserAction( REQUESTED_SAMPLE_WATER_USER_ACTIONS_T action )
+{
+    BOOL accepted = FALSE;
+    REQUEST_REJECT_REASON_CODE_T rejReason = REQUEST_REJECT_REASON_NONE;
+
+    // Reject user action requests if any alarm is currently active. User must clear alarm first.
+    if ( FALSE == isAnyAlarmActive() )
+    {
+        switch ( action )
+        {
+            case REQUESTED_USER_ACTION_SAMPLE_WATER_STOP:
+                if ( SAMPLE_WATER_STATE == currentSampleWaterState )
+                {
+                    sampleWaterStopRequested = TRUE;
+                    accepted = TRUE;
+                }
+                else
+                {
+                    rejReason = REQUEST_REJECT_REASON_ACTION_DISABLED_IN_CURRENT_STATE;
+                }
+                break;
+
+            case REQUESTED_USER_ACTION_SAMPLE_WATER_START:
+                if ( SAMPLE_WATER_STATE == currentSampleWaterState )
+                {
+                    sampleWaterStartRequested = TRUE;
+                    accepted = TRUE;
+                }
+                else
+                {
+                    rejReason = REQUEST_REJECT_REASON_ACTION_DISABLED_IN_CURRENT_STATE;
+                }
+                break;
+
+            default:
+                rejReason = REQUEST_REJECT_REASON_INVALID_COMMAND;
+                break;
+        }
+    }
+    else
+    {
+        rejReason = REQUEST_REJECT_REASON_ALARM_IS_ACTIVE;
+    }
+
+    sendSampleWaterCmdResponse( accepted, (U32)rejReason );
+}
+
+/*********************************************************************//**
+ * @brief
  * The handleWaterSampleSetupState function waits for filter flush period elapsed.
  * @details Inputs: flushTimerCounter
  * @details Outputs: none
Index: firmware/App/Modes/SampleWater.h
===================================================================
diff -u -rb6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7 -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Modes/SampleWater.h	(.../SampleWater.h)	(revision b6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7)
+++ firmware/App/Modes/SampleWater.h	(.../SampleWater.h)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -19,6 +19,7 @@
 #define __SAMPLE_WATER_H__
 
 #include "HDCommon.h"
+#include "HDDefs.h"
 
 /**
  *  @defgroup SampleWater SampleWater
@@ -39,6 +40,8 @@
 U32 getSampleWaterState( void );
 BOOL isSampleWaterPassed( void );
 
+void signalSampleWaterUserAction( REQUESTED_SAMPLE_WATER_USER_ACTIONS_T action );       // from user
+
 /**@}*/
 
 #endif
Index: firmware/App/Services/AlarmMgmt.c
===================================================================
diff -u -r766708fceb0bdf1af8c7897df29d4f5036bfd3db -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/AlarmMgmt.c	(.../AlarmMgmt.c)	(revision 766708fceb0bdf1af8c7897df29d4f5036bfd3db)
+++ firmware/App/Services/AlarmMgmt.c	(.../AlarmMgmt.c)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -528,6 +528,21 @@
 
 /*********************************************************************//**
  * @brief
+ * The isAnyAlarmActive function determines whether any alarm is currently
+ * active.
+ * @details Inputs: alarmStatus
+ * @details Outputs: none
+ * @return TRUE if given alarm is active, FALSE if not
+ *************************************************************************/
+BOOL isAnyAlarmActive( void )
+{
+    BOOL result = ( alarmStatus.alarmTop != ALARM_ID_NO_ALARM ? TRUE : FALSE );
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
  * The getCurrentAlarmStatePriority function determines the current alarm
  * state priority (NONE, LOW, MEDIUM, or HIGH).
  * @details Inputs: alarmStatus
Index: firmware/App/Services/AlarmMgmt.h
===================================================================
diff -u -rbc8403b288e167f51c9e991c2a07bb455c77c19a -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/AlarmMgmt.h	(.../AlarmMgmt.h)	(revision bc8403b288e167f51c9e991c2a07bb455c77c19a)
+++ firmware/App/Services/AlarmMgmt.h	(.../AlarmMgmt.h)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -262,6 +262,7 @@
 void signalAlarmSilence( U32 cmd );
 void signalAlarmUserActionInitiated( ALARM_USER_ACTION_T action );
 BOOL isAlarmActive( ALARM_ID_T alarm );
+BOOL isAnyAlarmActive( void );
 ALARM_PRIORITY_T getCurrentAlarmStatePriority( void );
 BOOL isAlarmRecoverable( ALARM_ID_T alarm );
 void setAlarmAudioVolume( U32 volumeLevel );
Index: firmware/App/Services/SystemComm.c
===================================================================
diff -u -r24a98ea92563dad552889c30604d539d266b339e -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 24a98ea92563dad552889c30604d539d266b339e)
+++ firmware/App/Services/SystemComm.c	(.../SystemComm.c)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -1195,6 +1195,10 @@
             handleUFVolumeSetRequest( message );
             break;
 
+        case MSG_ID_UI_SAMPLE_WATER_CMD:
+            handleSampleWaterCmd( message );
+            break;
+
         case MSG_ID_DG_COMMAND_RESPONSE:
             handleDGCmdResp( message );
             break;
Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -rb6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7 -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision b6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -30,6 +30,7 @@
 #include "ModeTreatmentParams.h"
 #include "PresOccl.h"
 #include "RTC.h"
+#include "SampleWater.h"
 #include "SafetyShutdown.h"
 #include "SystemComm.h"
 #include "SystemCommMessages.h"
@@ -471,8 +472,64 @@
     result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
 
     return result;
-}
+}
 
+/*********************************************************************//**
+ * @brief
+ * The handleSampleWaterCmd function handles a sample water user action command
+ * message from the UI.
+ * @details Inputs: none
+ * @details Outputs: message handled
+ * @param message a pointer to the message to handle
+ * @return none.
+ *************************************************************************/
+void handleSampleWaterCmd( MESSAGE_T *message )
+{
+    if ( sizeof( U32 ) == message->hdr.payloadLen )
+    {
+        U32 cmd;
+
+        memcpy( &cmd, &message->payload[0], sizeof( U32 ) );
+
+        signalSampleWaterUserAction( (REQUESTED_SAMPLE_WATER_USER_ACTIONS_T)cmd );
+    }
+    else
+    {
+        sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
+    }
+}
+
+/*********************************************************************//**
+ * @brief
+ * The sendSampleWaterCmdResponse function constructs a sample water user action
+ * response to the UI and queues the msg for transmit on the appropriate CAN channel.
+ * @details Inputs: none
+ * @details Outputs: Sample water command response msg constructed and queued.
+ * @param accepted T/F - was sample water request accepted?
+ * @param rejReason reason why request was rejected (or zero if accepted)
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendSampleWaterCmdResponse( BOOL accepted, U32 rejReason )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // Create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_HD_SAMPLE_WATER_CMD_RESPONSE;
+    msg.hdr.payloadLen = sizeof( BOOL ) + sizeof( U32 );
+
+    memcpy( payloadPtr, &accepted, sizeof( BOOL ) );
+    payloadPtr += sizeof( BOOL );
+    memcpy( payloadPtr, &rejReason, sizeof( U32 ) );
+
+    // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
+
+    return result;
+}
+
 /*********************************************************************//**
  * @brief
  * The sendDialysateTempTargetsToDG function constructs a dialysate temperature
Index: firmware/App/Services/SystemCommMessages.h
===================================================================
diff -u -rb6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7 -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision b6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7)
+++ firmware/App/Services/SystemCommMessages.h	(.../SystemCommMessages.h)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -158,6 +158,14 @@
 // MSG_ID_HD_PRESSURE_LIMITS_CHANGE_RESPONSE
 BOOL sendPressureLimitsChangeResponse( PRESSURE_LIMIT_CHANGE_RESPONSE_T *data );
 
+// MSG_ID_UI_SAMPLE_WATER_CMD
+void handleSampleWaterCmd( MESSAGE_T *message );
+
+// MSG_ID_HD_SAMPLE_WATER_CMD_RESPONSE
+BOOL sendSampleWaterCmdResponse( BOOL accepted, U32 rejReason );
+
+// *********** public DG command functions **********
+
 // MSG_ID_SET_DG_DIALYSATE_TEMP_TARGETS
 BOOL sendDialysateTempTargetsToDG( F32 primary, F32 trimmer );
 
@@ -188,6 +196,8 @@
 // MSG_ID_DG_OP_MODE
 void handleDGOpMode( MESSAGE_T *message );
 
+// *********** public data broad cast functions **********
+
 // MSG_ID_HD_ACCELEROMETER_DATA
 BOOL broadcastAccelData( F32 x, F32 y, F32 z, F32 xm, F32 ym, F32 zm, F32 xt, F32 yt, F32 zt );