A full assessment every year is justified only in 3 cases: if you are subject to CSRD, if you have made an SBTi or public net-zero commitment, or if your emissions vary substantially from year to year. In other situations, the most effective frequency combines a full assessment every 3 or 4 years and a light update in between, focused on scopes 1 and 2 and the 2 or 3 largest scope 3 emission categories. This cycle costs far less than a full annual assessment, for equivalent management.
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