1. Particulate matter (PM): PM refers to small particles of soot, ash, and other solid matter that are emitted from diesel engines. These particles can be harmful to human health as they can cause respiratory problems, heart disease, and cancer.
2. Nitrogen oxides (NOx): NOx refers to a group of gases, including nitric oxide (NO) and nitrogen dioxide (NO2), that are formed when nitrogen and oxygen in the air react at high temperatures. NOx emissions from diesel engines can contribute to smog formation, acid rain, and respiratory problems.
