Definitions of mass terminology

The following terms are used to refer to the different kinds of mass data that may be specified in the initial BoM, or calculated for a BoM item, when you run a Restricted Substances analysis.

Measured Mass

Mass data that has been specified for a BoM item as an absolute value (rather than as a percentage of the parent item).

• A Measured Mass can be specified in units of mass in the Quantity and Unit of Measure columns of the initial BoM.
• Alternatively, if the Quantity is specified using a non-mass unit, the Measured Mass can be calculated using additional information provided in the Mass per UoM and Mass unit columns of the initial BoM (see Specifying quantity and mass for a BoM item).

Mass calculated as a percentage

A mass that has been specified for a BoM item as a percentage (by weight) of its parent item (see Specifying quantity and mass for a BoM item), and then calculated from the mass of the parent item.

Note: A mass value can only be calculated if the parent has a ‘Measured Mass’, or if the mass of the parent item can itself be calculated as a % (by weight) of an item further up in the hierarchy that has a ‘Measured Mass’.

If the parent does not have a Measured Mass and there is insufficient data to calculate the parent’s mass as a percentage, then the BoM item will not have a ‘Mass calculated as a %’.

Reported Mass

A mass value that is calculated by the analysis and displayed in the analyzed BoM and Product Compliance report, that represents the total mass for the quantity of the item specified in the BoM, taking into account the quantities of parent assemblies.

For example, for a part in the BoM, the Reported Mass is for the number of parts specified in the Quantity column, multiplied by the Quantity of its parent assembly, and similarly by the Quantity of each of its ancestors in the BoM hierarchy.

Rolled-up Mass

A mass value that is calculated (where possible) for each BoM item, as the sum of the ‘Reported Mass’ values for each of the items immediately below it in the BoM.

Note: A Rolled-up Mass value will not be calculated if any of the sub-items has no ‘Reported Mass’ value available, or has been specified as a percentage (by weight) of its parent.

The Rolled-up Mass is for a single instance (or a single Unit of Measure) of the BoM item, and is displayed in the Rolled-up mass per UoM column of the analyzed BoM and the Product Compliance report.

• For BoM items that have a ‘Measured Mass’, the Rolled-up mass is used as a comparative mass check.
• For BoM items that have neither a ‘Measured Mass’ nor a ‘Mass calculated as a %’, the Rolled-up Mass (if available) is used as the source of the ‘Reported Mass’.