Source: Worksafe New Zealand
WorkSafe has published a consolidated version of the Health and Safety at Work (Hazardous Substances — Modified Application of Controlled Substance Licence Requirements for Specified Class 1 Substances) Safe Work Instrument 2023 on our website.
The consolidated safe work instrument (SWI) brings together the information from the principal (original) 2023 SWI and the 2025 amendment into one document, for ease of use.
This makes it easy to see all the additional class 1 (explosive) hazardous substances that require – or do not require – a controlled substance licence (CSL). Thirteen additional substances now require a CSL.
While the consolidated SWI is a useful summary, it is for reference only and is not the official version.
The principal SWI came into force on 25 September 2023, and the amendment SWI came into force on 30 June 2025. WorkSafe consulted with key stakeholders in the hazardous substances industry when both SWIs were proposed.
A CSL is required to possess certain class 1 explosive hazardous substances, as well as certain vertebrate toxic agents and fumigants. These substances need to be handled by people who have sufficient knowledge and practical skills and meet certain character requirements. A CSL is issued by WorkSafe under Part 7 of the Health and Safety at Work (Hazardous Substances) Regulations 2017 to applicants who meet the criteria. WorkSafe keeps a register of CSL holders.
Information about substances that require a CSL and how to apply for one: Controlled substance licences
