 Hi. Welcome to OISOM Academy. Let's begin with all you need to know about oxides of nitrogen. In atmospheric chemistry, NOx is a generic term to refer to the highly reactive poisoning gases composed of nitrogen and oxygen, namely nitric oxide and nitrogen dioxide. Nitrogen dioxide is a reddish brown acidic gas comprising one nitrogen atom and two oxygen atoms. It is a corrosive, strongly oxidizing and has a pungent irritating odor. Nitric oxide is a colorless gas consisting of one nitrogen atom bonded to one oxygen atom. It is oxidizing, non-flammable, poisonous gas with a slightly irritating odor. Now NOx is typically produced from the reaction of nitrogen and oxygen when fossil fuels are burned at high temperatures. From the total NOx released during combustion, 90% is nitric oxide. It rapidly reacts with oxygen in the atmosphere to form nitrogen dioxide which further forms ozone in presence of sunlight. The remaining NO2 eventually reacts with other substances in the air to form particulate matter, nitric acid and toxic organic nitrates such as peroxyacetyl nitrates. Emissions from vehicles such as cars, trucks, buses, boats, airplanes, etc. are the largest source of nitrogen oxides. Other sources are power plants, diesel powered heavy equipment, industrial boilers, petrol and metal refining, food processing and manufacturing industries, kerosene or gas heaters. Breathing air with a high NOx concentration can irritate the airways of human respiratory system. Exposures for a short period of time can aggravate respiratory diseases, particularly asthma, leading to respiratory systems such as coughing, wheezing or difficulty in breathing. It can further go to hospital admissions and visits to emergency rooms. Longer exposures may contribute to the development of asthma and potentially increase susceptibility to respiratory infections. Environmental impacts of NOx include formation of ozone, smog, acid rain, particulate matter, visibility impairment and water quality deterioration. Now NOx monitoring is an efficient way to prevent the accumulation of high levels of NOx as it helps detect the amount of NOx we are breathing in and alerts when a certain level is exceeded. Different walking principles for nitrogen oxide monitoring in the ambient environment are chemiluminescence, cavity attenuated phase shift spectroscopy or CAPS, semiconductor and electrochemistry. At ozone, we measure nitric oxide and nitrogen dioxide on principles of electrochemical sensing. It operates based on diffusion of NO and NO2 molecules into the respective sensor which results in the production of an electrical signal proportional to the nitric oxide and nitrogen dioxide concentrations respectively. Ozone's pollutron is an ambient air quality monitoring system capable of monitoring more than 30 parameters including gaseous pollutants like nitric oxide, nitrogen dioxide, carbon monoxide, carbon dioxide, sulphur dioxide, ozone, dust particulates like PM2.5, PM10, noise and weather parameters like rainfall, wind speed and wind direction. Real-time monitoring of nitric oxide and nitrogen dioxide levels helps in calculating air quality index to deliver health advisories as well as formulating an action plan to meet standards. Polludron is deployed across several cities, campuses, universities and is used for drawing actionable insights to tackle the rise in ambient nitrogen oxide concentrations. With this, I hope you now know all about nitric oxide and nitrogen oxide. For any questions or suggestions, please contact us. Thank you and happy learning.