Article 4 of Regulation (EU) No. 376/2014 defines the persons and organisations obliged to report occurrences under the “mandatory reporting system”. Personnel working at/for organisations approved in accordance with EASA Part 147 are not listed in paragraph 6 of article 4, therefore such organisations are not required to implement mandatory/ voluntary reporting systems according to Regulation (EU) No. 376/2014. This does not prevent any organisation or person involved in aviation activities, including maintenance training activities, to report any safety occurrence or other safety information they consider relevant.
Such reports would be to the voluntary reporting system to be established by all competent authorities according to Article 5.2 of Regulation (EU) No. 376/2014.
Typically a Part- 147 approved training organisation having implemented an Safety Management System (SMS) on a voluntary basis would have such a voluntary occurrence reporting system.
The European Commission (EC) published Guidance Material for Regulation EU No. 376/2014. Paragraph 3.3 further elaborates on the organisations affected by that regulation.
An online service developed by the EC allows organisations and individuals to report aviation safety occurrences to aviation authorities.