6.3.11.1 Due to the possible deviations when applying
the simplified measurement procedures of this chapter on board a ship,
an allowance of 10% of the applicable limit value may be accepted
for confirmation tests and periodical and intermediate surveys only.
6.3.11.2 The NOx emission of an engine
may vary depending on the ignition quality of the fuel and the fuel-bound
nitrogen. If there is insufficient information available on the influence
of the ignition quality on the NOx formation during the
combustion process and the fuel-bound nitrogen conversion rate also
depends on the engine efficiency, an allowance of 10% may be granted
for an on-board test run carried out on a RM-grade fuel (ISO 8217,
1996) except that there will be no allowance for the pre-certification
test on board. The fuel oil used shall be analysed for its composition
of carbon, hydrogen nitrogen, sulphur and, to the extent given in
ISO 8217, 1996, any additional components necessary for a clear specification
of the fuel.
6.3.11.3 In no case shall the total granted allowance
for both the simplification of measurements on board and the use of
heavy fuel oil of an ISO 8217, 1996, RM-grade fuel, exceed 15% of
the applicable limit value.