Index: Utilities.c
===================================================================
diff -u -r47f8ae76f4eed444ce98feec1635e62394afccf5 -rb65b35c0e1f3fd789707845d03e765a5ff4b5481
--- Utilities.c	(.../Utilities.c)	(revision 47f8ae76f4eed444ce98feec1635e62394afccf5)
+++ Utilities.c	(.../Utilities.c)	(revision b65b35c0e1f3fd789707845d03e765a5ff4b5481)
@@ -94,8 +94,8 @@
 static U32 timeWindowedCountsWindowMs[ NUM_OF_TIME_WINDOWED_COUNTS ];                       ///< Time windows (in ms) for time windowed counts
 static U32 timeWindowedCounts[ NUM_OF_TIME_WINDOWED_COUNTS ][ MAX_TIME_WINDOWED_COUNT ];    ///< Time stamps for instances for time windowed counts
 static U32 timeWindowedCountIndexes[ NUM_OF_TIME_WINDOWED_COUNTS ];                         ///< List indexes for time windowed counts
-static U32 timeWindowedCountCounts[ NUM_OF_TIME_WINDOWED_COUNTS ];                          ///< Current counts for time windowed counts
-
+static U32 timeWindowedCountCounts[ NUM_OF_TIME_WINDOWED_COUNTS ];                          ///< Current counts for time windowed counts
+
 /*********************************************************************//**
  * @brief
  * The crc16 function calculates a 16-bit CRC for a given range of bytes
@@ -265,7 +265,8 @@
     result = d.data;
     // verify data integrity
     if ( ( ~d.data.uInt != d.comp ) ||
-         ( TRUE != d.set ) ||
+         ( isCriticalDataInRange( &d ) != TRUE ) ||
+         ( d.set != TRUE ) ||
          ( data->typ >= NUM_OF_CRITICAL_DATA_TYPES ) )
     {
         result.uInt = 0;
@@ -281,24 +282,73 @@
 
 /*********************************************************************//**
  * @brief
+ * The isCriticalDataInRange function determines whether a critical data
+ * value is within the range set for that critical data.
+ * @details
+ * Inputs: none
+ * Outputs: none
+ * @param data Ptr to a critical data record
+ * @return TRUE if given data is in range, FALSE if not
+ *************************************************************************/
+BOOL isCriticalDataInRange( CRITICAL_DATA_T *data )
+{
+    BOOL result = FALSE;
+
+    if ( CRITICAL_DATA_TYPE_F32 == data->typ )
+    {
+        if ( ( data->data.sFlt >= data->minimum.sFlt ) && ( data->data.sFlt <= data->maximum.sFlt ) )
+        {
+            result = TRUE;
+        }
+    }
+    else if ( CRITICAL_DATA_TYPE_S32 == data->typ )
+    {
+        if ( ( data->data.sInt >= data->minimum.sInt ) && ( data->data.sInt <= data->maximum.sInt ) )
+        {
+            result = TRUE;
+        }
+    }
+    else
+    {
+        if ( ( data->data.uInt >= data->minimum.uInt ) && ( data->data.uInt <= data->maximum.uInt ) )
+        {
+            result = TRUE;
+        }
+    }
+
+    return result;
+}
+
+/*********************************************************************//**
+ * @brief
  * The setCriticalData function sets the value for a given critical data
  * record.
  * @details
  * Inputs: none
  * Outputs: alarm if HD critical error occurred
  * @param data Ptr to a critical data record
  * @param value a value to set
- * @return none
+ * @return TRUE if set was successful, FALSE if not (out of range)
  *************************************************************************/
-void setCriticalData( CRITICAL_DATA_T *data, CRITICAL_DATAS_T value )
+BOOL setCriticalData( CRITICAL_DATA_T *data, CRITICAL_DATAS_T value )
 {
+    BOOL result = FALSE;
+
     if ( data->typ < NUM_OF_CRITICAL_DATA_TYPES )
     {
-        _disable_IRQ();
-        data->data = value;
-        data->comp = ~data->data.uInt;
-        data->set = TRUE;
-        _enable_IRQ();
+        CRITICAL_DATA_T tmp = *data;
+
+        // test set on temporary data record so it can have its range pre-checked
+        tmp.data = value;
+        if ( TRUE == isCriticalDataInRange( &tmp ) )
+        {
+            _disable_IRQ();
+            data->data = value;
+            data->comp = ~data->data.uInt;
+            data->set = TRUE;
+            _enable_IRQ();
+            result = TRUE;
+        }
     }
     else
     {
@@ -308,22 +358,24 @@
         SET_ALARM_WITH_2_U32_DATA( ALARM_ID_HD_CRITICAL_DATA_ERROR, (U32)&data[0], 1 )
 #endif
     }
+
+    return result;
 }
 
 /*********************************************************************//**
  * @brief
  * The resetCriticalData function resets a critical data record.
  * @details
  * Inputs: none
- * Outputs: none
+ * Outputs: Given critical data record is reset to unset w/ default value.
  * @param data Ptr to a critical data record
  * @return none
  *************************************************************************/
 void resetCriticalData( CRITICAL_DATA_T *data )
 {
     _disable_IRQ();
     data->set = FALSE;
-    data->data.uInt = 0;
+    data->data.uInt = data->defValue.uInt;
     data->comp = ~data->data.uInt;
     _enable_IRQ();
 }
Index: Utilities.h
===================================================================
diff -u -re216986bd18d5272655ddb016eafb15e8b0bcfd6 -rb65b35c0e1f3fd789707845d03e765a5ff4b5481
--- Utilities.h	(.../Utilities.h)	(revision e216986bd18d5272655ddb016eafb15e8b0bcfd6)
+++ Utilities.h	(.../Utilities.h)	(revision b65b35c0e1f3fd789707845d03e765a5ff4b5481)
@@ -72,6 +72,9 @@
 typedef struct
 {
     CRITICAL_DATA_TYPES_T typ;  ///< Type of data
+    CRITICAL_DATAS_T minimum;   ///< Minimum value for valid data
+    CRITICAL_DATAS_T maximum;   ///< Maximum value for valid data
+    CRITICAL_DATAS_T defValue;  ///< Default value
     CRITICAL_DATAS_T data;      ///< Data value
     U32 comp;                   ///< One's compliment of value
     BOOL set;                   ///< Flag indicates data has been set
@@ -84,7 +87,8 @@
 void initTimeWindowedCount( TIME_WINDOWED_COUNT_T cnt, U32 maxCnt, U32 winMs );
 BOOL incTimeWindowedCount( TIME_WINDOWED_COUNT_T cnt );
 CRITICAL_DATAS_T getCriticalData( CRITICAL_DATA_T *data );
-void setCriticalData( CRITICAL_DATA_T *data, CRITICAL_DATAS_T value );
+BOOL setCriticalData( CRITICAL_DATA_T *data, CRITICAL_DATAS_T value );
+BOOL isCriticalDataInRange( CRITICAL_DATA_T *data );
 void resetCriticalData( CRITICAL_DATA_T *data );
 
 /**@}*/