Some Carriers ask shippers to confirm segregation group name for “N.O.S. Entries” which are not assigned to a segregation group. Should shippers provide Segregation Group Name to Carriers?

To answer these questions, we need to understand;

1. What is segregation group?
2. Who is responsible to provide the information, and
3. When this is required

What is segregation group?

 IMDG Code has two steps for checking compatibility between two or more dangerous goods, which are,

1. Segregation Table, and
2. Segregation Codes assigned in column 16b of Dangerous Goods List.

Segregation Table has six conclusions through the intersecting columns which are

1     “Away from”;

2     “Separated from”;

3     “Separated by a complete compartment or hold from”;

4     “Separated longitudinally by an intervening complete compartment or hold from”.

X   The Dangerous Goods List has to be consulted to verify whether there are specific segregation provisions

“ * ” See 7.2.7.1 of IMDG Code for the segregation provisions between class 1 substances or articles

In containerized transport whenever there is a segregation provision applicable between two goods they cannot be packed in same container unless for “away from” each other which may be packed together provided such consolidation is approved by the Competent Authority. (refer 7.3.4.1 of IMDG Code).

For Segregation of packages containing dangerous goods stowed in the conventional way refer to section 7.6.3.2 of IMDG Code

On board container ships segregation between containers are in accordance with below table (7.4.3.2 of IMDG Code)

Up to now we have discussed only part of the story, segregation table, and the meanings of terms 1 to 4.  However, we need to look into column 16b of Dangerous Goods list in Chapter 3.2 of IMDG Code before applying Segregation Table.

Segregation Codes

 The segregation codes, SG Codes, contain specific segregation requirements which will overrule the general segregation requirement in segregation table.

Three of SG Codes requirements are:

• Segregation as for class…..
• Stow “away from” class…..
• Stow “separated from” class….

This will take us back to segregation table.

Example UN 1732, Class 8(6.1) has below SG Codes in column 16b

• SG6 Segregation as for class 5.1
• SG8 Stow “away from” class 4.1
• SG10 Stow “away from” class 5.1
• SG12 Stow “away from” class 7

Other requirement of SG Codes will take us to segregation groups.

Example UN 3106 ORGANIC PEROXIDE TYPE D, SOLID, Class 5.2 has below SG Codes in column 16b

• SG35 Stow “separated from” acids.
• SG36 Stow “separated from” alkalis

Segregation Groups

For the purpose of segregation, dangerous goods having similar chemical properties have been grouped together in segregation groups. The entries allocated to these segregation groups are listed in section 3.1.4.4. of IMDG Code. There are total 18 segregation groups as below.

1. ACIDS
2. AMMONIUM COMPOUNDS
3. BROMATES
4. CHLORATES
5. CHLORITES
6. CYANIDES
7. HEAVY METALS AND THEIR SALTS (INCLUDING THEIR ORGANOMETALLIC COMPOUNDS)
8. HYPOCHLORITES
9. LEAD AND ITS COMPOUNDS
10. LIQUID HALOGENATED HYDROCARBONS
11. MERCURY AND MERCURY COMPOUNDS
12. NITRITES AND THEIR MIXTURES
13. PERCHLORATES
14. PERMANGANATES
15. POWDERED METALS
16. PEROXIDES
17. AZIDES
18. ALKALIS

Certain goods falling within the same class may fall in different segregation groups due to their nature of reacting dangerously with each other. Example Acids and Alkalis under class 8.

Mixing of chemicals of different segregation groups may cause dangerous reactions resulting in explosion, fire, release of flammable and or toxic gases or formation of unstable substances.

For general understanding below table specifies incompatibilities between the segregation groups.

IMDG Code has listed N.O.S. entries having proper shipping names specific for a family of chemical under segregation groups.

Example

Acid

1740  HYDROGENDIFLUORIDES, N.O.S.

3264  CORROSIVE LIQUID, ACIDIC, INORGANIC, N.O.S.

Powdered Metals

METAL POWDER, FLAMMABLE, N.O.S.

Akalis

3263  CORROSIVE SOLID, BASIC, ORGANIC, N.O.S

However, there are general N.O.S. entries which are not listed under segregation groups and which may be assigned by shipper to such chemical which has the properties of a segregation group.

Example

• 1759 CORROSIVE SOLID, N.O.S.
• 1760 CORROSIVE LIQUID, N.O.S.

If shipper is offering acid or alkali under UN 1759 or UN 1760 which are not assigned to segregation groups 1. Acid or 18. Alkali then it is the responsibility of the shipper to assign segregation group and inform carrier the group name.

The requirement of informing segregation group name to carrier is stipulated in section 7.2.5.3 of IMDG Code which states “It is recognized that not all substances, mixtures, solutions or preparations falling within a segregation group are listed in the IMDG Code by name. These are shipped under N.O.S. entries. Although these N.O.S. entries are not themselves listed in the segregation groups, the consignor shall decide whether inclusion under the segregation group is appropriate and, if so, shall mention that fact in the transport document.”

Section 5.4.1.5.11.1 of IMDG Code states “For substances, mixtures, solutions or preparations classified under N.O.S. entries not included in the segregation groups listed in 3.1.4.4 but belonging, in the opinion of the consignor, to one of these groups, the appropriate segregation group name preceded by the phrase “IMDG Code segregation group” shall be included in the transport document after the dangerous goods description. For example:  “UN 1760 CORROSIVE LIQUID, N.O.S. (Phosphoric acid, acetic acid) 8 III IMDG Code segregation group 1 – Acids”.”

 Conclusion

• Shipper need not provide segregation group names for single entries & specific N.O.S. entries already listed under segregation groups in section 3.1.4.4 of IMDG Code.
• Carrier may ask segregation group name for goods declared under general N.O.S. entries.
• Carrier will not ask segregation group name for goods declared under general N.O.S. entries and assigned to segregation group by shipper and this information is mentioned in transport document in accordance with section 5.4.1.5.11.1 of IMDG Code.

For Un Numbers assigned to segregation groups click here

Further readings