Simply speaking of "Parts Explosion", there are several interpretations, and thus the meaning is different depending on each usage. Generally speaking, it refers to the calculation of the parts' or materials' requirements in a production control system. Especially, it is often used for the calculation of requirements using a Product Summary B/M . When it refers to the method of explosion of B/M, it is used as a collective term of the following three methods:

Single Level Explosion:

one upper-level (parent) items or one lower-level (child) items of the item are searched.

Indented Explosion:

All upper-level or lower-level items are searched level by level.

Summarized Explosion:

all the upper-level or lower-level items are searched and the same parts are unified to one group.

In terms of explosion direction, in addition, there is another approach. Generally the explosion from lower to upper is called "Explosion" while the explosion from upper to lower is "Implosion". The Product Structure B/M is needed to perform such explosions. In computer systems, database is usually used to control bills of materials in a unified manner. See "Explosion method".

Related term: Bill of Materials,Explosion method