A help page for SONAR alerts (Policies > Virus and Spyware,,, > SONAR > SONAR Settings) says as following;

"Configures notifications to alert the user when SONAR makes a detection and the action is Quarantine or Remove."

An actual behavior, however, is that an alert for SONAR detection always happens regardless the action type, when it is turned on.

The help page is incorrect.  
The Sonar detection will pop up for Quarantine, Remove, and Log only. 

SEP14.0 MP2 will have updated help page which is along with actual behavior.

SEP12.1 version line won't have updated help page, but added a topic to the 12.1.6 MP8 release notes (and 14 MP2 release notes) as a correction.

Text in release notes will appear as follows; the last line is 14 MP2 only, since the 12.1.6 line won't get another Help update:

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Help erroneously indicates that alerts do not generate for all SONAR action 
types

The Help topic SONAR: SONAR incorrectly suggests that for When detection found, 
an alert does not appear when the action is Log only. An alert appears for all 
action types when a SONAR detection is made, not just for Quarantine or Remove. 
The corrected text for When detection found is as follows: 

     Configures notifications to alert the user when SONAR makes a detection. 

Updated Help text is slated to appear in a future release. 
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