A volume source of pollution is a three-dimensional source of pollutant emissions. Essentially, it is an area source with a third dimension.

Examples of a volume source of pollution are:

• Dust emissions from the wind erosion of uncovered gravel piles, sand piles, limestone piles, coal piles, etc.
• Fugitive gaseous emissions from pipe flanges, packed valve seals, gas compressor seals, control valve seals, piping and vessel seals within industrial facilities such as oil refineries and petrochemical plants.
• Buildings, containing air pollutant emission sources, with no singular emission vent (i.e., buildings with multiple roof vents or multiple open windows).