Chemical Regulation and Information Assistance

This Document aims to aid those who use hazardous substances

by providing information based on current New Zealand Law.  

Documents Referenced:

Hazardous Substances and New Organisms Act (1996)

The Chemical Weapons (Prohibition) Act 1996

WorkSafe - Working Safely with Hazardous substances Practical Guide

Over 100,000 businesses in New Zealand use, store and handle hazardous substances and must follow the strict laws and regulations outlined by the NZ government. With many deaths and injuries occurring due to businesses failing to follow the precautions and guidelines set out by the NZ government it is vital that this information is understood by all those who wish to use hazardous substances.

We have created an easy to follow summary of the free information provided by the New Zealand government to give you and your businesses a clear understanding of your obligations as users of hazardous substances.

If you are unsure about which controls are required for the hazardous substances you are using in your business, use the ‘WorkSafe’ hazardous substance calculator to help give you an idea.

Note* This document is only a simple guide and may not contain all of the information involved with Hazardous Substances. For more detailed information use the free guides provided by WorkSafe, MPI and other Government branches or take a look at the Hazardous Substances and New Organisms (HSNO) Act.

Hazardous Substances and New Organisms Act (1996)

What are Hazardous substances?

Hazardous substances are outlined by the Hazardous Substances and New Organisms (HSNO) Act (2016) to be any products or chemicals that are flammable, explosive, oxidizing, corrosive or toxic to the environment.

All Hazardous Substances that are manufactured, imported and sold in New Zealand must be authorized under the Hazardous Substances and New Organisms (HSNO) Act and are given an approval number which can be found on the ‘Material Safety Data Sheets’ provided by sellers and manufacturers. Approval numbers can also be found on the EPA ‘Approved Hazardous Substances with controls’ database, which can be found on the EPA website ‘

Hazardous substances Classifications

Products and chemicals are given a classification depending on the hazardous materials used to create them. This allows for the risks to be identified and managed accordingly. Classifications outlined by the HSNO Act are largely based on the dangerous good classification system outlined by the United Nations.

The classifications are as followed:

Class 1: explosives

Class 2: flammable gases

Class 3: Flammable liquids

Class 4: Flammable solids

Class 5: oxidizing substances

Class 6: substances toxic to people

Class 8: corrosive substances

Class 9: substances toxic to the environment

Note* Class 7 relates to radioactive substances that are regulated under the (Radioactive Safety Act 2016)

Some products may contain more than one classification due to the variants of materials used in their makeup.

Some Key Points For Managing Hazardous Substances

Managing Inventory

An inventory list must be created by each business that stores, manufactures and uses hazardous materials that will compile of all products covered under the HSNO Act. To help understand how to create an accurate inventory list for your businesses, related to hazardous materials see, ‘WorkSafe's inventory guide

This inventory list must be kept up to date, maintained accurately and easily available to emergency workers.

For more information, see section: 1.2 Hazardous Substances - Working safely with hazardous substances Practical Guide

Material Safety Data Sheets

Material Safety Data Sheets provide information on what materials are used in the makeup of the products and chemicals that are provided by sellers and manufacturers which, allows for accurate classification of the hazardous substances and how they affect health and safety.

For sore information, see section: 4.3 Safety data sheets - Working safely with hazardous substances Practical Guide

Risk Management

Once the hazardous substances are identified and compiled into an inventory list with all required safety data sheets, a facility using hazardous substances should look to minimize risks associated with these materials. This can be achieved by using ‘environmentally friendly’ substitutes, isolating hazards, creating physical and administrative controls and training and enforcing employees to use personal protective equipment and follow safety guidelines. For more detailed risk management precautions use the ‘WorkSafe's inventory guide

For more information, see section: 3.0 Manage hazardous substances risks - Working safely with hazardous substances Practical Guide

Labelling Containers

Products that contain hazardous substances need to have detailed labels attached that outline the materials present in the product so that users know exactly what it is inside. The labels must be easily readable and be provided by manufacturers, resellers for all stationary tanks, process containers, transportable containers and hazardous waste.

For more information, see section: 4.1 Label all Hazardous Substances - Working safely with hazardous substances Practical Guide


Signs provide information that identifies areas of concern for employees, visitors and emergency workers and other users of hazardous substances. Signs must be made from durable materials and be easily visible from 10 metres away and in English. There are specific regulations for each classification of hazardous substances.

For more information, see section: 4.4 Signage - Working safely with hazardous substances Practical Guide


Storage information is outlined on the safety data sheet that is provided along with the product. Hazardous Substances are stored in their original containers or if they are purchased in larger drums or tanks can be transferred into smaller containers to be mixed with other substances or for reselling. Containers used must be a material capable of storing that particular Hazardous substance it is being used for and must not have a food label attached to it, due to being mistaken for an edible substance.

For more information, see section: 5.1 Decanting or Transferring Substances - Working safely with hazardous substances Practical Guide


Having emergency response plans set out that relate to the particular Hazardous substances that business stores, will allow employees to react efficiently and reduce injuries and fatalities. The WorkSafe ‘Inventory Calculator’ provides information based on the inventory list created. Having spill kits on site, personal protective equipment, fire extinguishers and a well-organised emergency response plan will help prevent future accidents

For more information, see section:  6.3 Control measures in the hazardous substances calculator - Working safely with hazardous substances Practical Guide

Compliance Certificates

Compliance Certificates must be issued by independent service providers that are approved by WorkSafe to issue compliance certificates for handling, storing and using particular chemicals. Class 61.A and 61.B toxic substances and substances require a ‘certified substance licence, which includes explosives, fumigants and vertebrate toxic agents.

To find an approved certifier, head to WorkSafe's website:

For more information, see section: 7.0 Compliance Certificates - Working safely with hazardous substances Practical Guide

Tracking Very Hazardous Substances

Particular hazardous substances that enter New Zealand must be tracked from the time they enter the country right through until they are used and disposed of. Using the WorkSafe Calculator will identify which hazardous substances require tracking Only competent persons such as certified handlers or trained employees are able to handle Hazardous substances that require tracking. Competent persons are responsible for securing the substances throughout its lifetime and recording any transfers or movements.

For more information, see section: 8.4 Information needed in tracking records - Working safely with hazardous substances Practical Guide