Are they legally binding
Courts may regard a code of practice as evidence of what is known about a hazard, risk or control, and rely on it to determine what is 'reasonably practicable' in the circumstances to which the code relates.
It is recognised that equivalent or better ways of achieving the required work health and safety outcomes may be possible. For that reason compliance with codes of practice is not mandatory providing that any other method used provides an equivalent or higher standard of work health and safety than suggested by the code of practice.
Further, an inspector can refer to a code of practice when issuing an improvement or prohibition notice.