In brief
- Every workplace with hazardous substances needs an inventory, whatever the quantities.
- For each substance, record its name and UN number, the most you're likely to hold, where it's kept, its storage requirements and its safety data sheet.
- Update it whenever a product comes in, goes out or moves, and keep a copy where emergency services can reach it.
Most hazardous substances duties start at a set quantity. The inventory is different. Under regulation 3.1 of the Health and Safety at Work (Hazardous Substances) Regulations 2017, any business that manages or controls a workplace where hazardous substances are used, handled, manufactured or stored must prepare an inventory, keep it at the workplace and keep it up to date. It is one of the first things we ask to see at a certification visit, and the starting point for working out which other controls apply to you.
What the inventory must record
Regulation 3.1(2) lists what goes in it. For each hazardous substance:
- the product or chemical name, and the UN number if there is one
- the maximum quantity likely to be at the workplace
- where it is kept
- any specific storage and segregation requirements
- the current safety data sheet, or a condensed version of its key information
Hazardous waste goes in too, with an identifier that describes the waste as closely as possible, its maximum quantity, its location and any storage requirements.
A single line for petrol might read: petrol, UN 1203, 200 litres maximum, flammables cabinet in the workshop, keep away from oxidisers and ignition sources, current safety data sheet from the supplier filed with it.
Record the maximum quantity, not today's stock. If a 1,000 litre delivery arrives once a month, the inventory should show 1,000 litres even when the tank is half empty.
Keeping it current
The regulations don't set a review interval. They require the information to be up to date, and WorkSafe's guidance says to update the inventory whenever the information in it changes, including when you bring in a new product, stop using one, or move substances to a different location. Check it each time stock is ordered.
Where to keep the inventory
The inventory must be readily accessible to emergency service workers, including after the workplace has been evacuated. A copy in a weatherproof holder at the site entrance, or in the emergency response plan box, meets that better than a spreadsheet on the office computer.
Safety data sheets
A safety data sheet, or SDS, sets out a substance's hazards and how to handle, store and dispose of it. Regulation 2.11 requires you to:
- get the current SDS from the supplier when a substance is first supplied to the workplace, and again if the supplier amends it
- treat a substance as newly supplied if the workplace hasn't received it for five years, and get the current SDS again
- make the SDS, or its key information, readily accessible to workers in their work area and to emergency service workers
Mobile workers can rely on an SDS held at the main place of business, as long as they can get the key information immediately. There is no fixed age at which an SDS expires. The five-year rule is about re-supply.
What's exempt
Substances used only in quantities consistent with household use, such as a bottle of cleaning spray in the staff kitchen, don't need to go on the inventory. Commercial quantities of the same product do.
Penalties
Not keeping an inventory can bring a fine of up to $2,000 for an individual and $10,000 for a business. Safety data sheet breaches carry fines of up to $6,000 and $30,000.
Tools that help
WorkSafe's hazardous substances calculator builds an inventory as you enter your products and shows most of the controls that apply. The Hazardous Substances Toolbox workbook includes a printable inventory form. If you are preparing for a certification visit, a complete inventory with current safety data sheets is the most useful thing you can have ready. Ask us if you'd like us to review yours.
You can also start from our inventory template (fillable PDF), which has a column for each item regulation 3.1 requires.
This is general guidance based on the regulations and WorkSafe's published material. It is not legal advice.
Sources
- Health and Safety at Work (Hazardous Substances) Regulations 2017 (LI 2017/131), regs 2.11 and 3.1. New Zealand Legislation. Accessed 16 October 2026. https://www.legislation.govt.nz/regulation/public/2017/0131/latest/whole.html.
- WorkSafe New Zealand. "Inventory Requirements for Hazardous Substances." Quick guide, May 2019. Accessed 16 October 2026. https://www.worksafe.govt.nz/dmsdocument/2623-inventory-requirements-for-hazardous-substances-quick-guide/.
- WorkSafe New Zealand and MBIE. "Hazardous Substances Calculator." Hazardous Substances Toolbox. Accessed 16 October 2026. https://hazardoussubstances.govt.nz/calculator/.
- WorkSafe New Zealand. "Safety Data Sheets." Accessed 16 October 2026. https://www.worksafe.govt.nz/topic-and-industry/hazardous-substances/managing/safety-data-sheets/.