PDRs are currently exclusively used by Carnival (e.g CCL (Carnival Cruise Lines) , Holland Lines, and or CUK) for tracking training/assessments at various ranks as well as by vessel (e.g. 1st Engineering Officer; represented as "1EO", Vessel Britannia, PDR PDR1 = an instance of a PDR).
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CUK uses all types of the following PDRs. Currently the remainder of Carnival OLs Operating Lines (e.g. CCL, CMG, etc..) only use the Environmental PDRs (although this will most likely change)
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