You will need this approval if you intend to use a restricted chemical product (RCP).
Restricted chemical products are declared by the Australian Pesticides and Veterinary Medicines Authority (APVMA). These products are considered essential but inherently dangerous and consequently are strictly controlled.
You may need to undergo relevant training before an approval to use an RCP is granted.
An example of a RCP is copper chrome arsenate (CCA). This is a chemical used in the forestry industry to protect and preserve timber.