How does the calculation method differ for simple and complex goods?

Accounting for emissions of precursors in complex goods

For simple goods, the calculation focuses solely on the emissions occurring during their production.

For complex goods, the calculation must also include the embedded emissions of relevant precursors that are themselves CBAM goods. This means tracing the emissions through the supply chain. In some cases, a "bubble approach" can be used, where emissions are calculated jointly for a complex good and its precursor if they are produced in the same installation and the precursor is wholly used in the production of the complex good.