Index: firmware/App/Modes/ModePreTreat.c
===================================================================
diff -u -r981de1f5228152ec6877aceae3d66ebf5efc7101 -r27f3db92495948d4c1192421c1b0c20338c4a034
--- firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 981de1f5228152ec6877aceae3d66ebf5efc7101)
+++ firmware/App/Modes/ModePreTreat.c	(.../ModePreTreat.c)	(revision 27f3db92495948d4c1192421c1b0c20338c4a034)
@@ -16,6 +16,7 @@
 ***************************************************************************/
 
 #include "AlarmMgmt.h"
+#include "Buttons.h"
 #include "FPGA.h"
 #include "ModePreTreat.h"
 #include "OperationModes.h"
@@ -94,6 +95,13 @@
 *************************************************************************/
 U32 execPreTreatmentMode( void )
 {
+    BOOL stop = isStopButtonPressed();
+
+    if ( TRUE == stop )
+    {
+        activateAlarmNoData( ALARM_ID_TREATMENT_STOPPED_BY_USER );
+    }
+
     // execute mode state machine
     switch ( currentPreTreatmentState )
     {