Comments by "Rick2010100" (@Rick2010100) on "The Most Important Car Person You've Never Heard Of — Ferdinand Piëch — Jason Cammisa on the ICONS" video.

The NOx scandal was also no real scandal. The NOx regulation were introduced in the USA at the urging of the US car industry in order to force European diesel vehicles out of their market. NOx has a very short half-life of just a few hours, then the gas decomposes into ozone and other substances. The effect of NOx on humans is the same as ozone. However, the diesel exhaust gases do not reach the concentration of ozone that can naturally occur in sunny weather (splitting of molecular oxygen by UV radiation).
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