The maximum NOx emission threshold in Regulation 813/2013 has been established on the basis of data referring to the standard of 2009 and hence for a reference fuel with a nitrogen content of 140 mg/kg. Hence, despite the fact that the recent versions of the EN267 standard (EN267:2009+A1:2011 and EN267:2020) use for reference a fuel with a zero nitrogen content, the transitional method rightly indicates that the reference of 140 mg/kg should be used and how to correct the values resulting from the use of recent versions of EN267.
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