Our service uses combination branches on our hose lines, and has done for many years. I have been interested in the discussions about smooth bore v combination and have read a number of articles and viewed a number of training videos about the differences. It seems apparent that there are a number of advantages with solid streams, especially for a direct fire attack. Having had no practical experience with this type of nozzle (other than putting the combination onto a straight stream now and then), I have one nagging question regarding their suitability for interior firefighting. As a fire moves from the room of origin via overhead gases (convection) and travels to other areas within the structure, firefighters are often met having to deal with these superheated gases. Frequently a "roll over" condition exists, making advancing to the fire room hazardous, and flashover imminent. With our combination branches we have the spray pattern set on about 30 degrees and cool the overhead gases with controlled application (not too much water so as to overly disturb the thermal layers causing excessive steam) above and in front of us. The droplets of the spray absorb large amounts of heat as they covert to steam (the point at which water aborbs most heat). Water does not generally come into contact with the structure itself, and is just dealing with the gases. I have done this often in live fire training and at working jobs, and it has the effect of chasing the flames back into the room. Advancement can then be made to the fire room, where a direct attack with narrow spray can be made to extinguish the fire. This scenario most often occurs in hallways while moving down to the fire room in a house or apartment block. I can not imagine the smooth bore nozzle effectively achieving dealing with overhead rollover, although I'm sure it does. I'm interested to know how those of you with smooth bores deal with this situation. Are there any videos that demonstrate this, and do you think that the solid stream is as effective on overhead gas cooling? I'm not for one second doubting their effectiveness in these situations, but just have no experience with them and am very interested in finding out.