As the name suggests, stationary causes are ones that do not move. These would include primarily power and energy plants where oil or coal is refined or burned. Although we do need power for a myriad of reasons in our daily lives, the results of using these polluting forms of the power generation process release many dangerous chemicals into the air.
One of the most common of these chemicals is sulfur dioxide. When coal and other fuel sources are burned, this chemical is released and can have damaging effects on the people in the surrounding areas. When present in low concentrations, the compound is not extremely dangerous. However, the concentrations around these plants can be very high and that can lead to serious breathing problems in the residents of surrounding areas. Of course, the wind also moves these concentrations of sulfur dioxide where they begin to mix with a host of other pollutants in the air; spreading the pollution and causing problems for areas far away from the plants.