In the UK we are governed by the CAA and JAR.
All airlines have to follow certain safety standards in order to be able to operate.
This includes ensuring all crew have received adequate training to cover all eventualities such as evacuation, ditching (water landing), decompression (loss of cabin air pressure). Crew are also trained in medical emergencies.
Each new crew member has to sit an exmination covering all of these subjets as well as practical excercises.
Then before they can operate must complete a minimum of 2 take offs and two landings in a crew position seat, whilst not actually officially operating as crew.
Prior to each flight, crew have to answer safety and medical questions. If they do not get them correct, subject to the decision of the airline, they do not fly and then re-sit the exams.
Once a year, crew then take a refresher course to ensure they are up-to-date.
Some airlines adopt their own regulations but these must be based around those set by the UK CAA.
Hope that helps!
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