Article 19 of Regulation (EU) 2016/1628, provides for monitoring of the gaseous pollutant emissions by testing in-service engines installed in non-road mobile machinery and operated over their normal operating duty cycles.

In order to ensure the monitoring provided for in Article 19, it is necessary to adopt detailed arrangements with regard to the selection of engines, test procedures and reporting of results.

In order to reduce the administrative burden for small volume manufacturers and for manufacturers producing a limited number of engine types or engine families, it is necessary to limit the number of engines subject to in-service monitoring testing by those manufacturers.

To ensure coherence in the application of this Regulation, the manufacturer should not be required to present in-service monitoring test results if it can demonstrate that the engines have not been installed in non-road mobile machinery or that it was not able to obtain access to an engine in any application for testing.

In order to further harmonise the in-service monitoring procedures for non-road mobile machinery with other EU legislation and international standards, those procedures should be aligned with in-service conformity check for heavy-duty vehicles (EURO VI) and with the requirements of Regulation 96 adopted by the United Nations Economic Commission for Europe,