FE/BR is an abbreviation for the term "Forced Entry and Ballistic Resistance"

This term is commonly found in standards and requirements set forth by the DOS (Department of State)
and FBO (Department of Foreign Buildings Operations); now known as OBO (Overseas Buildings Operations).

DOS policy establishes the following three levels of forced entry protection:

• 5 minutes,

• 15 minutes,

• 60 minutes.

• DOS policy establishes military rifles as the levels of ballistic protection required.

• The shotgun is used to test the ballistic vulnerability of any convoluted
  passages, such as deal trays.