Smoke Cloud Phases. Smoke-producing devices produce smoke clouds of various sizes and
densities. Once a smoke cloud is produced, its life may be described in four successive phases (Figure
a. Streamer Phase. In this phase the smoke streamers move downwind from the smoke sources
and begin to expand.
b. Buildup Phase. This phase occurs when the individual streamers begin to merge. The
distribution of smoke is not uniform at this stage.
c. Uniform Phase. In this phase the streamers merge into a smoke cloud of uniform density.
The extent of this phase is determined by weather conditions, wind, and terrain.
d. Terminal Phase. As the smoke moves downwind, it thins and dissipates. This phase occurs
at the extent of the smoke cloud when it is no longer effective.
Figure 1-16. Four phases of a smoke cloud
During mobile smoke operations the movement of the smoke vehicles will produce a uniform smoke
cloud by merging the streamers. The smoke cloud will be moved downwind and will have a terminal
phase. The continuous movement of the smoke vehicles will keep the smoke cloud uniform. The
smoke vehicle maneuver routes may have to be adjusted depending on the wind and weather conditions.