ISO/FDIS 21575

FINAL DRAFT
International
Standard
ISO/TC 172/SC 3
Raw optical glass — Powder test
Secretariat: JISC
method for the water resistance of
Voting begins on:
optical glass — Test method and
2025-10-28
classification
Voting terminates on:
2025-12-23
Verre optique brut — Méthode d'essai sur poudre pour
déterminer la résistance à l'eau du verre optique — Méthode
d'essai et classification
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Reference number
FINAL DRAFT
International
Standard
ISO/TC 172/SC 3
Raw optical glass — Powder test
Secretariat: JISC
method for the water resistance of
Voting begins on:
optical glass — Test method and
classification
Voting terminates on:
Verre optique brut — Méthode d'essai sur poudre pour
déterminer la résistance à l'eau du verre optique — Méthode
d'essai et classification
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
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BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
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Published in Switzerland Reference number
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principles . 1
5 Reagents . 1
6 Apparatus . 2
7 Preparation of the specimen of the glass to be tested . 3
8 Procedure . 4
9 Classification and designation . 4
10 Test report . 5

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
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with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee SC 3,
Optical materials and components.
This second edition cancels and replaces the first edition (ISO 21575:2018), which has been technically
revised.
The main changes are as follows:
— change of title;
— the term “weight” has been changed to “mass” in the entire document;
— 5.1 and 6.1 have been added;
— Figure 3 has been added;
— the information required for the test report has been revised;
— editorial changes;
— the term
...