Exploding the Bill of Materials 
Use
If you have allocated a material with a bill of material (BOM), a sales order BOM, or a WBS BOM to an activity, you can explode this BOM in the network level-by-level or completely (multi-level).
If the material component was already allocated to the activity before the BOM explosion, you have the following options.
Procedure
The BOM selection dialog box appears.

If you explode the BOM all at once, requirements could be generated both in the network and in MRP, depending on control of the BOM items. Since MRP always explodes the complete BOM, this could lead to multiple requirements for the same component.
A list of all the BOM items appears.

Document items are not includes in this list, since the system does not copy document items to network activities.
See also:
BOM transfer