1.   The column allows the ascending vapour to come into contact with the descending liquid.

2.   This column allows the identifiers of any superseded DCs to be specified.

3.   This column allows the names of the modules which are to be changed for this DC to be specified.

4.   This column allows the identifiers of the related SPRs to be specified.

5.   This column allows the identifiers of any related DCs to be specified.

6.   This column allows the identifiers of the new DCs to be entered.

7.   This column allows the identifiers of any related Issues to be specified.

8.   This column allows the names of the affected modules to be specified.

9.   This column allows the issue number of the first version of the specified module to be entered.