Standards for the specification of tolerances for glass material imperfections have been evolving over the past 40 years. Today, several individual ISO Standards for drawings and drawing notation − ISO 10110-2, ISO-10110-3, and ISO- 10110-4, which were last revised in 1996 and 1997 − are being merged and re-written to incorporate technical improvements and enhance the clarity of presentation. The new standard, tentatively numbered ISO 10110-18, is on schedule for release in 2018. It will also provide notation to directly utilize concepts and quality classes defined in ISO 12123, the newly revised standard for raw glass material. New ways to specify striae and a way to specify raw material specifications on a finished part drawing are two additional highlights of the revised versions of this set of ISO standards. This paper will discuss the old shortcomings, their corrections, and the new features incorporated into the set of standards currently under final development and whose publication is expected next year.
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