The Industrial Chemicals Act (2019) puts the onus directly on you to declare how risky your chemical is.

Degrees of risk are ...

• Very low - Exempted - requires a Post-Introduction Declaration to AICIS
• Low - Reported (also Reported<=10Kg) - requires a Pre-Introduction Report to AICIS to approve introduction
• Medium to high - Assessed - requires a paid AICIS assessment prior to introduction

The General Rules and AICIS Guidelines spell out in detail how to categorise that risk. They also specify studies and information required to support categorisation.

And of course you don't have to categorise nor even tell AICIS you are introducing it if your chemical is...

• Listed - already on the AICIS Inventory with standard or particular obligations or restrictions on Introduction

But, listed chemicals occasionally get re-evaluated. AICIS publishes changes and Chemintro keeps track. That means if your chemicals are involved, Chemintro will email you to keep you in the loop.