As Cordo watches, the Fourth Doctor is trapped in a cubicle that begins to fill with balerium gas. (TV: The Sun Makers)
Consum Banks were used on Pluto for the transfer of money via consumcards. The banks contained cubicles that processed the cards, transferring the talmar value.
The Fourth Doctor was sent to the Consum Bank on subway 37 by Mandrel to collect a thousand talmars from a consumcard. When he entered a cubicle, it locked down and began to fill with balerium gas that knocked him unconscious. Men then came and took him away on a stretcher. (TV: The Sun Makers)