A Level 6 security clearance, sometimes called a Level 6 authorization clearance, granted the holder access to information about the OSI's bionic program. Though most often used to indicate credentials held by an employee of the OSI, it was a more general security class for use in other divisions of the Executive Branch of the United States Government. What other information Level 6 holders might have been entitled to see is unclear.
The ordinal scale of the various levels of clearance was never examined in detail. However it is known that Oscar Goldman's secretaries held Level 4 clearance within their first week of working at the OSI. ("Steve Austin, Fugitive") Also, Lt. Col. Harry Donner had a Level 5 clearance, which seemed sufficient to allow him to talk to Steve Austin in a secure building, but not to gain access to the area of the building most critical Dr. Rudy Wells' bionic laboratory. ("Wine, Women and War" - the first time a security clearance level was mentioned). Josh Perkins' Level 5 was likewise deemed not high enough for sharing the bionic secret — Steve tells him "I'm classified six." ("Little Orphan Airplane") Dr. Rudy Wells was known to have a Level 7 clearance ("Kill Oscar").
Steve and Jaime frequently "grant" persons with lower clearance Level 6, by virtue of showing them some bionic feat. This is doubtless not an actual raise of clearance for most, but it does seem to have stuck for Callahan ("Steve Austin, Fugitive"). In some cases, this is accompanied by the order that the witness forget what they've seen, for the rest of their lives ("Wine, Women and War"). Steve seems to vary on his interpretation of the seriousness of the security clearance, such as when he rather casually discusses his bionics with fellow astronauts Vasily Zhukov ("Doomsday, and Counting") and Kelly Woods ("The Rescue of Athena One"). In the case of the former, it could be argued that Austin actually committed treason by revealing his bionics to the Russian (as well as to a second Russian officer in the same episode). It's possible, however, that astronauts (and cosmonauts) might, for some reason, have Level 6 clearance.
In the vernacular, security clearances were often referred to in reverse of how they were written. Thus, the written Level 6 authorization clearance (in some versions of The Bionic Woman opening credits) might be spoken, "6 Level".
- The use of security clearances in "Kill Oscar" seems at variance with its usage in other episodes. There, differentiation is made between an "OSI" clearance and an "NSB" clearance. Rudy's citation of a Level 7 clearance to stay in the room with the NSB search for Oscar is not deemed sufficient by Jack Hanson because it is "an OSI clearance." In "H＋2＋O = Death", a character claims a security clearance level of 12 and is later revealed to be working with OSI security.
- Security clearance levels appear to have been restructured or loosened by the time of the reunion films, as a wider net of OSI employees appear to be aware of bionics by this time.
In SMDM: Season Six issue #3, MASKATron recognizes that Oliver Spencer has a Level 8 OSI security clearance.