When i applied, we had assessments first, followed by an interview to those who passed the assessments.
They posted me practice materials i think which i no longer have at hand. From what i remember, one of the tests involves listening to a recording where you will hear a series of sounds (Woman yelling "Train is ready to depart", beep followed by honk or something like that) and a question being asked by a customer.
The safety aspect is noting the order in which the sounds are played, because you need to be able to dispatch the train safely. There is only one correct order. The customers question poses as a distraction. You need to be able to mark on your answer sheet whether the train is ready to depart or not, and also answer the customers question.
Of course, most importantly you should correctly answer whether the train can depart or not. Answering the customers question correctly is 2nd in priority (but still important as you want the marks!).
Additionally there is another assessment where you have to read paragraphs of text and answer questions with A, B, C or D. They're testing how well you follow instructions and take in information correctly.
