7.Primary or secondary: keep them apart

Primary and secondary metal have very different emissions, so keep them separate wherever the data is known. The split also affects the free allocation adjustment, which uses the (K) or (L) benchmark. A remelter that blends secondary metal with bought primary ingot should track the two flows from the start.

Sources: G5e §2.2.3.3 p.16; FAA Annex point 3.3.