The key to understanding the beauty of how the Dualmist System works and also how low pressure watermist works in general is to try to understand the why the droplet size range is so important.

In the chart below you can see that the range of droplet sizes produced by the Dualmist System is in between that of sprinklers and high pressure systems.

With high pressure systems - a very fine mist/aerosol is produced which is very effective at heat suppression but not so good at high ceiling heights or in open areas as side draft can cause the vapor to be swept sideways away from the fire. With high pressure systems there is little surface wetting due to the droplets evaporating before they reach the fire or nearby heated surfaces.

Conversely with sprinkler systems there is a huge amount of surface wetting but very little heat suppression as there is very little mist produced and little to stop the heat spreading across the ceiling cavity by convection which is where most of the heat from the fire ends up. With sprinklers there is also no mechanism to stop heat transfer across the room from radiating burning/hot objects and even worse with sprinklers most of the water quickly ends up on the floor and is then effectively useless from a suppression point of view. The length of time the the water droplets spend in the air is a critical factor in heat suppression. Please take a moment to study the below chart as it is of critical importance in terms of understanding how the system works.

As shown, the dualmist system produces the range of droplet sizes in between both.

This means the system produces both mist for heat suppression and coarser droplets for surface and wall wetting. Some of these larger droplets spray high up onto the walls and then run down the walls keeping them cool. They also have the benefit of helping to distribute the smaller droplets away from the nozzle head. The fine droplets stay airborn for a prolonged period of time until most eventually evaporate and expand into inert gas (water vapor) displacing the air in the room and thus reducing the percent oxygen levels which in turn reduces the overall burn rate of the fire. The dualmist nozzles use a combination of all the above methods to suppress the fire.

As you can see for a 2.5 height room there is an optimum range of droplet size to produce both effects. For higher height rooms the optimum range droplet size moves upwards accordingly.