Slough-Windsor-Datchet-Heathrow-Southall hazes of the 1980s

NOx
NOx gases are usually produced from the reaction among nitrogen and oxygen during combustion of fuels, such as hydrocarbons, in air; especially at high temperatures, such as occur in car engines. In areas of high motor vehicle traffic, such as in large cities, the nitrogen oxides emitted can be a significant source of air pollution. Small amounts of NOx gases are also produced naturally by lightning.

The event
Slough-Windsor-Datchet-Heathrow-Southall hazes of the 1980s was a unpleasant, but minor air pollution incident in the county of Surrey. It was photogenic haze (a mild form of smog) that occurred on a few days during the mid to late 1980s due to some perticly hot and still summer weather, which allowed London's drifting car fumes (including a lot of NOx and diesel particulates), local high car and factory fume levels to mix in to a mildly toxic ground level 'haze' cloud.

Also see

 * 1) Photogenic smog
 * 2) The Great London Smog of 1952
 * 3) Central London hazes of the 1990s and 2010s
 * 4) Slough-Windsor-Datchet-Heathrow-Southall hazes of the 1980s