Steve, I'm guessing your not in the USA? If I'm right, then I'll go on an assume that you probably don't have many structures that are built entirely out of wood?
The wood frame construction causes us to operate differently. If the structure is all masonry then the fire fuel consists of the contents,. This means that though the fire can and is quite dangerous it can be successfully suppressed with steam that is produced by a fog nozzle. Since a wood structure also has a large attic space, also constructed entirely out of wood a large combustible void is ever present. The main fire stopping feature in our houses is gypsum wall board, also called sheetrock. It does a good job for a short time but once the fire gets around it, we're off to the races.
Americans like big fluffy furniture that creates an extreme amount of fuel that also produces a wicked toxis smoke. If a fire starts and the occupants are asleep, their only hope of self evacuating is a loud smoke detector and hopefully light enough sleepers that wake up hearing the alarm. If they don't self rescue, then it is up to us. Though steam can/will suppress fire propogation it also creates havoc for trapped victims, in other words, the steam will kill them. So with that and many other things I haven't mentioned, we must employ an aggressive form of ventilation that permits the toxic fumes to exit before they build up inside the structure killing the victims. We also have to get that smoke out before it creates a flashover. The smoke in our fires can flashover in temperatures as low as 600 Farenhiet. We have used the steam method in the past but it is having less and less effectiveness due to our constructuoin methods. Therefore we have had to switch to a solid stream in order to extinguish the fires and also have a chance for rescue