Source: U.S. Environmental Protection Agency
quote: As an example, most diesel sold in western countries is ULSD (ultra low sulphur), where it's defined as 15 ppm. Now that the US has sulfur similar standards, diesel engines don't have to be redesigned to enter the US (hence more models becoming available). Unless you've done extensive research in the field, you have no basis for saying a 10 ppm standard is unduly burdensome.
quote: Sulfur differs from carbon in much more meaningfully ways than color. I have to question if you even passed highschool when you're making such a ludicrous analogy. Chemical methods can eliminate impurities to less than 1 ppm in many different materials.