There is nothing in the CSA guidelines regarding the refresher training for trainers. The 3 years is for operators only. CSA B335-4, 6.21.1 Chapter 7 refers to trainers and there is not a word regarding refresher training.
****, there are trainers out there who should not even be training in the first place, but I won't name any in case they are reading this thread.
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.