A recent test was done on what attacking a fire using 1 3/4" hose with a Phantom fog attached to a 7/8" slug tip. What we found made us rethink how we fight fires in a high rise with this nozzle. What is compartmentalization? Has the study on modern fuels or changes in building construction changed the definition of a residential high rise once thought to be compartmentalized by Chief O'Hagen in 1977?