(1)  A medical practitioner must not, for the purposes of this Act, assess the degree of a person's permanent impairment, unless the medical practitioner has been accredited by the Board to assess the degree of a worker's permanent impairment.

(2)  .  .  .  .  .  .  .  .  

(3)  A person is not to provide a prescribed service in respect of an injury for which compensation is or may be payable under this Act unless the person belongs to a class of persons prescribed in relation to the prescribed service and that person has been accredited by the Board.

(4)  A person (in this section referred to as a "provider" ) is not to provide workplace rehabilitation services to another person for the purposes of this Act (including by reason only of supplying to the other person the services of a person employed or engaged by the provider) unless the provider has been accredited by the Board as a workplace rehabilitation provider.

(5)  Subsection (4) does not apply to a person, employed or engaged by the provider, who provides services to another person on behalf of the provider, if the provider is accredited by the Board.