This column tells the worst risk detected on a particular machine.
Possible values are as follows: "0" being the most worst and "15" being the least worst detection on the machine.
0 = (Severity 0) Viral
1 = (Severity 1) Non-Viral malicious
2 = (Severity 2) Malicious
3 = (Severity 3) Antivirus - Heuristic
5 = (Severity 5) Hack tool
6 = (Severity 6) Spyware
7 = (Severity 7) Trackware
8 = (Severity 8) Dialer
9 = (Severity 9) Remote access
10 = (Severity 10) Adware
11 = (Severity 11) Jokeware
12 = (Severity 12) Client compliancy
13 = (Severity 13) Generic load point
14 = (Severity 14) Proactive Threat Scan - Heuristic
15 = (Severity 15) Cookie
9999 = No detections
Check page 209 on the document at the following link.
ftp://ftp.symantec.com/public/english_us_canada/products/symantec_endpoint_protection/11.0/manuals/mr2/schema_reference_guide.pdf