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Hazardous substances classification codes

Hazard classifications are communicated on labels and safety data sheets including the safe way to store, use and dispose of chemicals.

We use the Globally Harmonised System (GHS 7) hazard classification system in New Zealand. 

The GHS 7 assigns classifications to a hazardous substance based on its:

  • physical hazards (such as flammability)
  • human health hazards (such as acute toxicity)
  • environmental hazards (such as whether it is hazardous to the aquatic environment). 

A hazard classification comes in two parts:

  1. The hazard class – this refers to the nature of the hazard the substance poses, and are grouped into physical, health or environmental hazards
  2. The hazard category – this refers to hazard severity within a hazard class; the lower the category number the more severe the hazard.

For example:

  • Acute oral toxicity Category 1: acute oral toxicity is the hazard class, Category 1 is the category.
  • A substance with the hazard classification acute oral toxicity Category 1 is more toxic than a substance with the hazard classification acute oral toxicity Category 4.

Some of the hazard classes have sub categories, types, divisions or groups, as well as or instead of categories. These can differ based on severity, how the substance is packaged, or on various physical properties.

The correlation tables below list the hazard classifications and their correlation to the previous HSNO classification system used. These table are also available as a PDF:

HSNO to GHS7 Correlation table (PDF, 241 KB)

You can refer to the chemical classification and information database (CCID) which holds hazard information for single chemicals, including the hazard classification, study summaries and physical properties of a substance.

Physical hazards Plus

HSNO classification – pre-GHS 7 adoption 

HSNO classification – post-GHS 7 adoption

Explosives (class 1)
  unstable explosive
1.1 (A, B, C, D, E, F, G, J, L) 1.1 (A, B, C, D, E, F, G, J, L)
1.2 (B, C, D, E, F, G, H, J, K, L) 1.2 (B, C, D, E, F, G, H, J, K, L)
1.3 (C, F, G, H, J, K, L) 1.3 (C, F, G, H, J, K, L)
1.4 (B, C, D, E, F, G, S) 1.4 (B, C, D, E, F, G, S)
1.5D 1.5D
1.6N 1.6N

Flammable gases
2.1.1A

flammable gas Category 1A

flammable gas Category 1A pyrophoric gas

flammable gas Category 1A chemically unstable gas A

flammable gas Category 1A chemically unstable gas B

flammable gas Category 1B

Note: Some flammable gases Category 1A may be additionally classified as pyrophoric and/or chemically unstable.
2.1.1B flammable gas Category 2

Aerosols
2.1.2A (flammable aerosol) aerosol Category 1
aerosol Category 2 
  aerosol Category 3

Gases under pressure
 

compressed gas

liquefied gas

refrigerated liquefied gas

dissolved gas

Flammable liquids
3.1A flammable liquids Category 1
3.1B flammable liquids Category 2
3.1C flammable liquids Category 3
3.1D flammable liquids Category 4

Desensitised explosives

3.2A (liquid) and 4.1.3A (solid)

3.2B (liquid) and 4.1.3B (solid)

3.2C (liquid) and 4.1.3C (solid)

 desensitised explosive Category 1
desensitised explosive Category 2
desensitised explosive Category 3
desensitised explosive Category 4

Flammable solids
4.1.1A flammable solids Category 1
4.1.1B flammable solids Category 2

Self-reactive substances and mixtures
4.1.2A self-reactive substances and mixtures Type A
4.1.2B self-reactive substances and mixtures Type B
4.1.2C self-reactive substances and mixtures Type C
4.1.2D self-reactive substances and mixtures Type D
4.1.2E self-reactive substances and mixtures Type E
4.1.2F self-reactive substances and mixtures Type F
4.1.2G self-reactive substances and mixtures Type G

Pyrophoric liquids, pyrophoric solids, self-heating substances and mixtures
4.2A pyrophoric liquids Category 1, or
pyrophoric solids Category 1
4.2B self-heating substances and mixtures Category 1
4.2C self-heating substances and mixtures Category 2

Substances and mixtures which, in contact with water, emit flammable gases
4.3A substances and mixtures which, in contact with water, emit flammable gases Category 1
4.3B substances and mixtures which, in contact with water, emit flammable gases Category 2
4.3C substances and mixtures which, in contact with water, emit flammable gases Category 3

Oxidising substances that are liquids or solids
5.1.1A oxidising liquids Category 1, or
oxidising solids Category 1
5.1.1B oxidising liquids Category 2, or
oxidising solids Category 2
5.1.1C oxidising liquids Category 3, or
oxidising solids Category 3

Oxidising gases
5.1.2A oxidising gases Category 1

Organic peroxides
5.2A organic peroxide Type A
5.2B organic peroxide Type B
5.2C organic peroxide Type C
5.2D organic peroxide Type D
5.2E organic peroxide Type E
5.2F organic peroxide Type F
5.2G organic peroxide Type G

Corrosive to metals
8.1A corrosive to metals Category 1
Health hazards Plus

HSNO classification – Pre-GHS 7 adoption

HSNO classification – Post-GHS 7 adoption

Acute toxicity
6.1A (oral, dermal, inhalation) acute oral toxicity Category 1
acute dermal toxicity Category 1
acute inhalation toxicity Category 1
6.1B (oral, dermal, inhalation) acute oral toxicity Category 2
acute dermal toxicity Category 2
acute inhalation toxicity Category 2
6.1C (oral, dermal, inhalation) acute oral toxicity Category 3
acute dermal toxicity Category 3
acute inhalation toxicity Category 3
6.1D (oral, dermal, inhalation) acute oral toxicity Category 4
acute dermal toxicity Category 4
acute inhalation toxicity Category 4
6.1E (oral, dermal, inhalation) Note: acute toxicity Category 5 has not been adopted

Aspiration hazard
6.1E (aspiration hazard) aspiration hazard Category 1
Note: aspiration hazard Category 2 has not been adopted

Respiratory tract irritation
6.1E (respiratory tract irritant) specific target organ toxicity – single exposure Category 3 respiratory tract irritation

Skin corrosion/irritation
8.2A skin corrosion Category 1A
8.2B skin corrosion Category 1B
8.2C skin corrosion Category 1C
6.3A skin irritation Category 2
6.3B Note: skin irritation Category 3 has not been adopted

Serious eye damage/eye irritation
8.3A serious eye damage Category 1
6.4A eye irritation Category 2
Note: The subcategories 2A and 2B have not been adopted

Respiratory or skin sensitisation
6.5A respiratory sensitisation Category 1
6.5B skin sensitisation Category 1

Germ cell mutagenicity
6.6A germ cell mutagenicity Category 1
6.6B germ cell mutagenicity Category 2

Carcinogenicity
6.7A carcinogenicity Category 1
6.7B carcinogenicity Category 2

Reproductive toxicity
6.8A reproductive toxicity Category 1
6.8B reproductive toxicity Category 2
6.8C (additional category for effects on or via lactation) effects on or via lactation

Specific target organ toxicity
6.9A (oral, dermal, inhalation) specific target organ toxicity – single exposure Category 1
specific target organ toxicity – repeated exposure Category 1
6.9B (oral, dermal, inhalation) specific target organ toxicity – single exposure Category 2
specific target organ toxicity – repeated exposure Category 2
6.9B (narcotic effects) specific target organ toxicity – single exposure Category 3 narcotic effects
Environmental hazards Plus

HNO classification – pre-GHS 7 adoption

HSNO classification – post-GHS 7 adoption

Hazardous to the aquatic environment
9.1A hazardous to the aquatic environment acute Category 1
hazardous to the aquatic environment chronic Category 1
9.1B hazardous to the aquatic environment chronic Category 2
9.1C hazardous to the aquatic environment chronic Category 3
9.1D hazardous to the aquatic environment chronic Category 4
Note: hazardous to the aquatic environment acute Category 2 and acute Category 3 have not been adopted

Hazardous to the terrestrial environment
9.2A, 9.2B, 9.2C, 9.2D hazardous to soil organisms
9.3A, 9.3B, 9.3C hazardous to terrestrial vertebrates
9.4A, 9.4B, 9.4C hazardous to terrestrial invertebrates
9.1D (designed for biocidal action) designed for biocidal action
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