See Fair Work Act s.789FC(1)
For a worker to be able to apply to the Commission for orders to stop bullying or sexual harassment (or both), the worker must reasonably believe that they have been bullied and/or sexually harassed at work.
The expression ‘reasonable belief’ and similar expressions are used in a wide variety of contexts by the statutory and common law. It is clear from cases decided in those differing contexts that not only must the requisite belief actually and genuinely be held by the relevant person, but in addition the belief must be reasonable in the sense that, objectively speaking, there must be something to support it or some other rational basis for the holding of the belief. It will not be a reasonable belief if it is irrational or absurd.