Brooyn Dispatcher would contact HP Pumping Station to turn HP systen on when 10-30s (working fire) or 10-75 or multiple alarm was transmitted. Also at discretion of dispatcher for some boxes or additional information received. Dispatcher would then notify responding units and 43 BN HP system was being activated.Just a bit off the subject, many years ago assignment cards for lower Manhattan and Coney Island in Brooklyn had "H.P." next to the box number to designate a high pressure hydrant area.