The emission value obtained by the direct monitoring and
measurement method should be compared to the NOx emission limit value
as given in regulation 13 of
Annex VI, plus allowance values as given in the NOx Technical Code, paragraphs 6.3.11.1, 6.3.11.2 and 6.3.11.3 in
order to verify that an engine continues to comply with the requirements
of regulation 13 of Annex VI.