Together, NO and NO2 are known as NOX. This is released into the atmosphere when fuels are burned (for example, petrol or diesel in a car engine, or natural gas in a domestic central- heating boiler or power station). NO2 can affect our health. There is evidence that high levels of it can inflame the airways in our lungs and, over a long period of time, affect how well our lungs work. People with asthma are particularly affected. NO2 can also affect vegetation.
NO2 and the UK
Air Quality Strategy
The concentration of NO2 is measured in micrograms in each cubic metre of air (μg m-3). A microgram (μg) is one millionth of a gram. A concentration of 1 μg m-3 means that one cubic metre of air contains one microgram of pollutant. To protect our health, the UK Governments set two air quality objectives for NO2 in their Air Quality Strategy:
NOX emissions from burning fossil fuels are mainly as NO, but some sources can release a lot of NOX as NO2. These primary NO2 emissions are particularly important from diesel vehicles (especially when moving slowly as in our centre), and can make up as much as 25% of the total NOX emissions from this source. One reason for this is as a side-effect of measures that have been developed to reduce emissions of particulate matter from diesel vehicles by treating the exhaust using diesel particulate filters. These primary NO2 emissions can lead to high concentrations of NO2 at the roadside, especially where there are many diesel vehicles.
Hillingdon sees highest increase in air pollution deaths http://www.airqualitynews.com/2013/11/06/hillingdon-sees-highest-increase-in-air-pollution-deaths/