From Marine Personnel Regulations.
103 (3) The successful completion of a course that was taken for the purpose of obtaining a certificate of competency or an endorsement remains valid for life once that certificate or endorsement has been obtained, except in the case of the following courses:
(c) a course with respect to tankers;
and section 165 (2) An applicant for renewal of a Specialized Oil Tanker Training endorsement shall meet the requirements set out in column 1 of the table to this subsection and the corresponding specifications set out in column 2.
Item Column 1 Column 2
1 Experience The following service within the 5 years before the application date for renewal, if the applicant has not obtained the training certificate referred to in item 2:
(a) at least 3 months on board one or more oil tankers performing duties relating to the loading, discharging or transferring of cargo and the operation of cargo equipment; or
(b) at least 24 months as
(i) a shore captain or marine superintendent in charge of supervising the loading or unloading of oil tankers, or
(ii) an instructor at a recognized institution having taught at least two approved training courses in specialized oil tanker safety.
Certificate to be provided to the examiner
If the applicant has not acquired the experience set out in item 1, a specialized oil tanker safety training certificate obtained within the 5 years before the application date for renewal.
So if you do not have 3 months on a tanker in the past 5 years, you have to retake the advanced courses again.
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