The protocol sets limits on emissions of sulphur dioxide (SO₂), non-methane volatile organic carbon (NMVOC), ammonia (NH₃) and nitrogen oxides (NOx ).

Norwegian emission ceilings for 2020, given as reductions from 2005 in per cent:

SO₂ : 10 per cent

NO_X : 23 per cent

NH₃ : 8 per cent

NMVOC: 40 per cent