BZ as a chemical agent abbreviation
The NATO uses the abbreviation BZ for one other purpose.
Its code for the odorless and nonirritating incapacitating agent "3-Quinuclidinyl benzilate (QNB)" is BZ (Wikipedia). This `psycho-chemical' agent acts as an antagonist of muscarinic acetylcholine receptors and was tested by the U.S. Army from 1955 until 1975 at its Edgewood Arsenal in Maryland. It was discovered by the Swiss pharmaceutical company Hoffman-LaRoche in 1951 while investigating new anti-spasmodic agents but was found unsuitable for their purposes. By 1989, all remaining BZ stocks were destroyed during the general downsizing of the U.S. Army's chemical warfare program.