The goal is to deliver a comprehensive and technically detailedspecification using proven technology validated by careful technical scrutiny and rigorous testing.
Assessment for that is mainly done within a school but follows a detailedspecification - with marks deducted for dragging crimpers when applying almond paste, for example.
While the octane specification of a particular grade is constant throughout the year, the RVP specification changes with the seasons. (See Refining 101: Winter Gasoline for a more detailed explanation of gasoline blends).