A brush discharge is a type of corona discharge that takes place between two electrodes embedded
in a non-conducting medium (e.g. air at atmospheric pressure) and is characterized by non-sparking,
faintly luciferous furcations composed of ionized particles.
Brush discharges can occur from charged insulating plastics (for example polyethene) to a
conductor. The maximum energy associated with brush discharges is unlikely to exceed 4 mJ.
Such discharges may be incendive but are less likely to cause ignition of a solvent-air mixture
than an electrostatic discharge between two conductors.
A spark discharge is another form of electrostatics which occurs between two
conductive bodies carrying different potentials.