What is the segregation in IMDG code ? how do you do it for container ship ?

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IMDG code Vol1 chapter 7.2 on Segregation gives all the information on segregation.
Basically there are 4 types of segregation-

1 - Away from - Effectively segregated so that the incompatible goods cannot interact dangerously in the event of an accident but may be transported in the same compartment or hold or on deck, provided a minimum horizontal separation of 3 metres, projected vertically, is obtained.

2 - Separated from- In different compartments or holds when stowed under deck. Provided the intervening deck is resistant to fire and liquid, a vertical separation, i.e. in different compartments, may be accepted as equivalent to this segregation. For on deck stowage, this segregation means a separation by a distance of at least 6 metres horizontally.

3 - Separated by a complete compartment or hold from - Either a vertical or a horizontal separation. If the intervening decks are not resistant to fire and liquid, then only a longitudinal separation, i.e. by an intervening complete compartment or hold, is acceptable. For on deck stowage, this segregation means a separation by a distance of at least 12 metres horizontally. The same distance has to be applied if one package is stowed on deck and the other one in an upper compartment.

4 - Separated longitudinally by an intervening complete compartment or hold from - Vertical separation alone does not meet this requirement. Between a package under deck and one on deck, a minimum distance of 24 metres,including a complete compartment, must be maintained longitudinally. For on deck stowage, this segregation means a separation by a distance of at least 24 metres longitudinally.

A Segregation table is given which shows the general provisions for segregation between the various classes of dangerous goods.
SINCE THE PROPERTIES OF SUBSTANCES, MATERIALS OR ARTICLES WITHIN EACH CLASS MAY
VARY GREATLY, THE DANGEROUS GOODS LIST SHALL ALWAYS BE CONSULTED FOR PARTICULAR
PROVISIONS FOR SEGREGATION AS, IN THE CASE OF CONFLICTING PROVISIONS, THESE TAKE
PRECEDENCE OVER THE GENERAL PROVISIONS.
SEGREGATION SHALL ALSO TAKE ACCOUNT OF A SINGLE SUBSIDIARY RISK LABEL.

For the purposes of the segregation provisions for the various means of transport by sea, this chapter has
been subdivided as follows:
.1 segregation of packages:
.2 segregation of cargo transport units on board container ships:
.3 segregation of cargo transport units on board roll-on/roll-off ships:
.4 segregation in shipborne barges and on board barge-carrying ships:
.5 segregation between bulk materials possessing chemical hazards and dangerous goods in packaged
form


For segregation of DG on container ships 2 tables are given as below-

Table of segregation of freight containers on board container ships
Table of segregation of cargo transport units on board hatchless container ships

After identyfying the segregation provision from the general table the applicable container table is refered for close vs close, close vs open or open vs open both vertical and horizontally which gives the required container space in between.

Container space means a distance of not less than 6 m fore and aft or not less than 2.4 m athwartships.