Road vehicles and agricultural vehicles have both been using ULSD for the past 10 or so years in America, and it's my impression that this is common elsewhere in the developed world too. ULSD has two orders of magnitude less sulfur than common jet fuel.

Kathmandu is far from this, by the way. IIRC a major component of the smog was from smugglers adulterating the fuel, e.g. adding kerosene to gasoline.