|Syntax and mark-up / Procedures and steps|
Task topics can only contain one procedure, with one continuous set of numbered steps.
The task information type is specifically designed to contain one procedure only. If you feel you need to document two procedures in one task topic, you should re-examine your approach. Two procedures should be documented in two task topics.
If necessary, you can output two DITA task topics to one single output HTML topic, using the chunk attribute.
If you feel that you need to restart numbering within a task, then you probably have more than one procedure in the topic, and should split them into two separate task topics.
In some cases, what appears to be two procedures may turn out to be a nested procedure, in which case the substeps element can be used. The choicetable structure is also useful for procedures where a step has a number of alternative options.
If a procedure can be performed in two different ways, you should document those alternatives in two separate topics.