Definition - What does Primary Pollutants mean?
Primary pollutants are emissions that directly cause air pollution in the form in which they are released at the source. Certain primary pollutants can react with other elements or compounds, creating new chemicals that are known as secondary pollutants.
Safeopedia explains Primary Pollutants
The list of primary pollutants overlaps with the EPAs list of criteria pollutants. Primary pollutants include carbon monoxide, oxides of nitrogen, sulfur oxides, volatile organic compounds (VOCs) and particulate pollution such as dust, ash or salt particles. Recent emissions control measures in the US are becoming increasingly stringent, and industries are held accountable if they exceed the agreed acceptable emissions limits for primary pollutants. These restrictions on pollution are likely to become even more strict in coming years as the US strives to reduce its emissions and improve air quality.