The TAU was designed to combat main and auxiliary space Bravo class fires using a combination of PKP to knock down the flames and AFFF to cover the fuel source. These units were located to cover the evacuation of watch standers in case the fire grew out of control. Originally designed and installed before bilge sprinkling they took the place of installed duplex proportioners.  

The twin agent unit consisted of a 50 foot hose reel containing a 1 and ½ inch hard rubber AFFF hose and ¾ inch PKP hose. These were supplied by a 50 gallon AFFF station located on the DC deck and a 125 lb bottle of PKP located next to the hose reel in the engineering space.