Hazardous substances that activate key safety controls

The Health and Safety at Work (Hazardous Substances) Regulations 2017 (the Regulations) bring together the health and safety requirements for using hazardous substances at work. These new Regulations sit under the Health and Safety at Work Act 2015 (HSWA).

The Regulations set controls for safely managing your hazardous substances based on the hazard classifications of the substances and the amounts held in one place.

This guide is written for persons conducting a business or undertaking (PCBUs) who use, handle, manufacture and store hazardous substances. In this guide ‘you’ means the PCBU. A PCBU may be an individual person or an organisation, such as a business entity.

For more information about the PCBU, see our guide:

Introduction to the Health and Safety at Work Act 2015 - special guide (PDF 519 KB)

Note: This guide does not relate to Class 1, explosive substances, any variations to specific substances or variations made to specific situations such as farms.

1.0 The total amount of all your substances may activate controls

This guide gives you a summary of the amounts (thresholds) of substances with certain classifications that activate a particular control. Controls are rules put in place to prevent or manage the harm that hazardous substances can cause. However, in practice, many of the requirements you must follow are determined by the combined total amount of hazardous substances with different classifications onsite. This guide can therefore only give you general information.

The hazardous substances calculator can help you

The Hazardous Substances Calculator(external link) is an electronic tool that can help you work out the key safety controls you need to follow for all of the hazardous substances you use and store at your workplace. See www.hazardoussubstances.govt.nz(external link) for more information.

2.0 Certified handlers

A certified handler is someone who has a current compliance certificate to show that they have received the information, training and instruction that they need to handle highly hazardous substances.

Do you need a certified handler?

You need a certified handler if your workplace handles any amount of substances requiring a controlled substance licence (CSL) or have an acutely toxic (6.1A or 6.1B) classification. Substances that need a CSL include most fumigants and some vertebrate toxic agents (VTAs).

For more information about being certified to handle hazardous substances see certified handlers.

For more information about being licensed to possess certain explosives, vertebrate toxic agents or fumigants, see controlled substances licenses

3.0 Amounts of substances that must be secured when unattended

Highly hazardous substances or large amounts equal to, or over, the amounts in the table below must be secured from people not permitted by the PCBU to have access to them when they are unattended.

Hazard of classification (HSNO) of substanceSubstance must be secured when amount is equal to or over the amounts below
2.1.1A 100 kg (non-permanent gas) or 100 m3 (permanent gas) permanent gas
2.1.2A 3,000 L (aggregate water capacity)
3.1A Any amount
3.1B

250 L when in containers of more than 5 L or

500 L when in containers less than or 5 L in size

3.2A Any amount
3.2B 100 L
4.1.1A 100 kg
4.1.2A, 4.1.2B Any amount
4.1.2C, 4.1.2D 25 kg
4.1.2E, 4.1.2F 50 kg
4.1.3A Any amount
4.1.3B 100 kg
4.2A Any amount
4.2B 100 kg
4.3A Any amount
4.3B 100 kg
5.1.1A Any amount
5.1.1B 500 kg or 500 L
5.1.1C 1,000 kg or 1,000 L
5.1.2A 250 kg or 200 m3
5.2A, 5.2B Any amount
5.2C, 5.2D, 5.2E, 5.2F 10 kg or 10 L
6.1A, 6.1B Any amount (must be either under the personal control of a certified handler or secured)
6.1C Any amount (except for classes 1.1C (UN 0160) and 1.3C (UN 0161)
Anhydrous ammonia (HSNO approval number HSR001035) 100 kg
6.7A 10 kg or 10 L
8.2A Any amount

4.0 Location compliance certificates

A current compliance certificate is needed at hazardous substance locations where flammable, oxidising, toxic or corrosive substances are stored or used and the amount of substance is over the amounts in Table 2 below.

If no specific amount is listed for open or closed containers then the amount is the same whether the substance is in an open container or a closed container.

Hazard classification (HSNO) of substanceLocation compliance certificate needed when have amounts of substance over those below
2.1.1A , 2.1.1B 100 kg or 100 m3 for a permanent gas
2.1.2A 3,000 L (aggregate water capacity)
3.1A 20 L

3.1A
(petrol, aviation gasoline, and racing gasoline)

50 L
3.1B

Closed containers
100 L (in containers more than 5 L in size) or
250 L (in containers 5 L or less in size)

Open containers
50 L

3.1C

500 L (in containers more than 5 L in size) or
1,500 L (in containers 5 L or less in size)

Open containers
250 L

3.2A, 3.2B, 3.2C 1 L
4.1.1A 1 kg
4.1.1B 100 kg

4.1.2A, 4.1.2B

1 kg 
4.1.2C, 4.1.2D 25 kg
4.1.2E, 4.1.2F, 4.1.2G 50 kg
4.1.3A, 4.1.3B, 4.1.3C 1 kg
4.2A 1 kg
4.2B, 4.2C 25 kg
4.3A 1 kg
4.3B 25 kg
4.3C 50 kg
5.1.1A 50 kg or 50 L
5.1.1B 500 kg or 500 L
5.1.1C 1,000 kg or 1,000 L
5.1.2A 100 kg non-permanent gas or 200 m3 permanent gas
Oxygen in discrete cylinder or tank –HSR001029 200 m3
Chlorine – HSR1001058 150 kg
5.2A, 5.2B 10 kg
5.2C, 5.2D 25 kg
5.2E, 5.2F 100 kg
6.1A 50 kg or 50 L
6.1B 250 kg or 250 L
6.1C 1,000 kg or 1,000 L
8.2A 50 kg or 50 L
8.2B 250 kg or 250 L

Note: Location compliance certificates are required for class 6 and 8 substances from 1 December 2019.

For more information, see location compliance certificates.

5.0 Emergency management, secondary containment and signs

If you have hazardous substances at your site, you need to put measures in place so that if an incident or emergency happens, you can reduce the effects.

What measures you need in place depends on the amount of hazardous substances you have and the classification of those substances.

Fire extinguishers

 If you have flammable or oxidising substances in amounts over those in the table below, you must have fire extinguishers at your workplace. In some cases you will need two fire extinguishers. Fire extinguishers must have a minimum rating of 30B5 and must be readily available and accessible in an emergency.

Hazard classification (HSNO) of substanceFire extinguisher needed when amounts over those belowNumber of fire extinguishers required
2.1.1A

50 kg non-permanent gas or 30 m3 permanent gas

1
2.1.1B

200 kg non-permanent gas or 120 m3 permanent gas

2
2.1.2A 3,000 L aggregate water capacity 1
3.1A 50 L 1
  200 L 2
3.1B 250 L 2
3.1C, 3.1D 500 L 2
3.2A, 3.2B, 3.2C 50 L 1
  200 L 2
4.1.1A 250 kg 2
4.1.1B 500 kg 2
4.1.2A, 4.1.2B, 4.1.2C, 4.1.2D, 4.1.2E, 4.1.2F, 4.1.2G  50 kg or 50 L 1
  200 kg or 200 L 2
4.1.3A, 4.1.3B, 4.1.3C 50 kg or 50 L 1
  200 kg or 200 L 2
4.2A 50 kg or 50 L 1
  200 kg or 200 L 2
4.2B 250 kg or 250 L 2
4.2C 500 kg or 500 L 2
4.3A 50 kg or 50 L 1
  200 kg or 200 L 2
4.3B 250 kg or 250 L 2
4.3C 500 kg 500 L 2
5.1.1A 5 kg or 5 L 1
  25 kg or 25 L 2
5.1.1B 200 kg or 200 L 1
  500 kg 500 L 2
5.1.1C 500 kg or 500 L 2
5.1.2A 10 kg non-permanent gas or 10 m3 permanent gas 1
  50 kg non-permanent gas or 50 m3 permanent gas 2
5.2A, 5.2B 1 kg or 1 L 1
5.2C, 5.2D 10 kg or 10 L 1
5.2E, 5.2F 50 kg or 50 L 1

Signs

Signs let emergency services, workers and other people know about the presence of hazardous substances. If you have amounts of hazardous substances over the amounts in the table below, you must have signs at your workplace.

Hazard classification (HSNO) of substanceSigns needed when have amounts over those below
2.1.1A 250 kg non-permanent gas or 100 m3 permanent gas
2.1.1B 500 kg non-permanent gas or 200 m3 permanent gas
2.1.2A 3,000 L aggregate water capacity
3.1A 50 L
3.1B 250 L
3.1C 1,000 L
3.1D 10,000 L
3.2A 50 kg or 50 L
3.2B 250 kg or 250 L
3.2C 1,000 kg or 1,000 L
4.1.1A 250 kg
4.1.1B 1,000 kg
4.1.2A, 4.1.2B 50 kg or 50 L
4.1.2C, 4.1.2D 250 kg or 250 L
4.1.2E, 4.1.2F, 4.1.2G 1,000 kg or 1,000 L
4.1.3A 50 kg or 50 L
4.1.3B 250 kg or 250 L
4.1.3C 1,000 kg or 1,000 L
4.2A 50 kg or 50 L
4.2B 250 kg or 250 L
4.2C 1,000 kg or 1,000 L
4.3A 50 kg or 50 L
4.3B 250 kg or 250 L
4.3C 1,000 kg or 1,000 L
5.1.1A 50 kg or 50 L
5.1.1B 500 kg or 500 L
5.1.1C 1,000 kg
5.1.2A 250 kg non-permanent gas or 500 m3 permanent gas
5.2A, 5.2B 1 kg or 1 L
5.2C, 5.2D, 5.2E, 5.2F 10 kg or 10 L
6.1A 5 kg non-permanent gas or 2.5 m3 permanent gas
  50 kg or 50 L
6.1B 5 kg non-permanent gas or 2.5 m3 permanent gas
  250 kg or 250 L
6.1C 5 kg non-permanent gas or 2.5 m3 permanent gas
  1,000 kg or 1,000 L
6.1D 10,000 kg or 10,000 L
8.1A 1,000 kg or 1,000 L
  Aerosol 3,000 L aggregate water capacity
8.2A 5 kg non-permanent gas or 2.5 m3 permanent gas
  50 kg or 50 L
8.2B 50 kg non-permanent gas or 25 m3 permanent gas
  250 kg or 250 L
8.2C 1,000 kg or 1,000 L
  Aerosol 3,000 L aggregate water capacity
8.3A 1,000 kg or 1,000 L
  Aerosol 3,000 L aggregate water capacity
9.1A 100 kg or 100 L
9.1B, 9.1C 1,000 kg or 1,000 L
9.1D 10,000 kg or 10,000 L

For more information, see hazardous substance signs.

Emergency response plans and secondary containment

Emergency response plans

If your workplace has large amounts of hazardous substances, you will need to have an emergency response plan that covers all of the emergencies that have a realistic chance of happening involving those substances. The plan should also cover all of the hazardous substances that are likely to be in the workplace. If you have substances in amounts over those in Table 5, you will require an emergency response plan.

For more information, see emergency plans

Secondary containment

A secondary containment system can contain liquids if there is a spill and prevent or reduce hazardous substances from getting into the environment, drains or waterways. If you have substances with the classification and amounts shown in Table 5 and those substances are liquids or will liquefy in a fire you will need secondary containment.

Hazard classification (HSNO) of substanceEmergency response plan and secondary containment needed when have amounts over those below
2.1.1A 300 kg non-permanent gas or 200 m3 permanent gas
2.1.1B 1,000 kg non-permanent gas or 600 m3 permanent gas
2.1.2A 3,000 L aggregate water capacity
3.1A 100 L
3.1B 1,000 L
3.1C, 3.1D 10,000 L
3.2A, 3.2B, 3.2C 100 L
4.1.1A 1,000 kg
4.1.1B 10,000 kg
4.1.2A, 4.1.2B 50 kg or 50 L
4.1.2C, 4.1.2D 100 kg solid or 100 L
4.1.2E, 4.1.2F, 4.1.2G 200 kg or 200 L
4.1.3A, 4.1.3B, 4.1.3C 100 kg or 100 L
4.2A 100 kg or 100 L
4.2B 1,000 kg
4.2C 10,000 kg
4.3A 100 kg or 100 L
4.3B 1,000 kg or 1,000 L
4.3C 10,000 kg or 10,000 L
5.1.1A 50 kg or 50 L
5.1.1B 500 kg or 500 L
5.1.1C 5,000 kg or 5,000 L
5.1.2A 100 kg non-permanent gas or 100 m3 permanent gas
5.2A, 5.2B 10 kg or 10 L
5.2C, 5.2D 25 kg or 25 L
5.2E, 5.2F 100 kg or 100 L
6.1A, 6.1B, 6.1C 5 kg non-permanent gas or 2.5 m3 permanent gas
  100 kg or 100 L
6.1D, 6.5A, 6.5B, 6.7A 50 kg non-permanent gas or 25 m3 permanent gas
  Aerosol 3,000 L aggregate water capacity
  1,000 kg or 1,000 L
6.6A, 6.7B, 6.8A, 6.9A 10,000 kg or 10,000 L
8.2A 5 kg non-permanent gas or 2.5 m3 permanent gas
  100 kg or 100 L
8.2B 50 kg non-permanent gas or 25 m3 permanent gas
 

1,000 kg or 1,000 L
Aerosol – 3,000 L water capacity

8.2C, 8.3A

10,000 kg or 10,000 L
Aerosol – 3,000 L water capacity

9.1A 100 kg or 100 L
9.1B, 9.1C 1,000 kg or 1,000 L
9.1D 10,000 kg or 10,000 L

 

6.0 Tracking hazardous substances

Tracking ensures that a highly hazardous substance is under the control of a well-trained person or is secure from access by unauthorised people at all times.

Tracked substances can only be transferred to a competent person. A competent person is a certified handler or someone who has been trained to handle, use and store that substance safely.

Any amount of a substance with one or more of the following classifications requires tracking. Some VTAs and fumigants also require tracking. You can use the Hazardous Substances Calculator(external link) to find out whether a substance needs
to be tracked.

Substances with these classifications require tracking

3.1A, 3.2A
4.1.2A, 4.1.2B
4.1.3A
4.2A
4.3A
5.1.1A
5.2A, 5.2B
6.1A, 6.1B

For more information, see tracking hazardous substances