The Ingredients page of an MDS displays a tree structure which includes parent-child
relationships. “Layers” are represented by indentations. Many sub-elements may visually
separate items at the same layer. Although IMDS will permit different element types at the same
layer, recommendations specify having only one element type per layer. The MDS types have a
hierarchy which allows only certain children under a specific parent node:
• Components may have components, semi-components, and materials as children.
• Semi-Components may have other semi-components and materials as children.
• Materials may have other materials or basic substances as children.
• Basic substances may not have children.
The following figure displays a representative component tree structure.
In this figure, owned component