The Infocomm Media Development Authority of Singapore (IMDA) has issued a circular updating the requirements for the revalidation of GMDSS General Operator Certificate (GOC) and Restricted Operator Certificates (ROC).
The certificates of competency for ship station operators issued by the IMDA are in accordance with the requirements of Radio regulations of the International Telecommunication Union and the STCW Convention of the IMO.
The holder of a certificate of competency for ship station...
https://safety4sea.com/imda-update-on-revalidation-of-gmdss-certificates/