Similarly to translators, interpreters may be EU officials (or work as external freelancers). To be part of the core staff, the same EPSO competition must be passed as for anyone else. In the annual cycle, the linguist and interpreter exams are announced in the summer, usually around June or July of the year.
Abstract, verbal and numerical reasoning tests must be passed, along with a live translation or interpreting exercise, group exercise, a structured interview and possibly a case study as well.
See also:
Translators, Assessment Centre, Verbal Reasoning, Numerical Reasoning, Abstract Reasoning, Freelance Translators