Electrostatic precipitation after a storm is when a machine is used to filter out particles in the air. This is often used after a storm because sometimes storms can pollute the air and make it unhealthy for people to breathe. The machine uses a process called electrostatics, which uses electricity to help attract particles in the air and filter them out. The particles are collected in a special compartment where they can be disposed of safely so they won't hurt people or the environment.