ISO 21575:2018 pdf free
ISO 21575:2018 pdf free.Optics and photonics一Optical materials and components
The configuration and dimensions of the apparatus are shown in Figure 2. However, the dimensions of Figure 2 are merely an example, the shape shall conform to ISO 4797 and ISO 4799. The dimension and shape may be different, as long as the nominal capacity of a spherical-shaped flask is 100 ml. The apparatus shall employ a flask fitted to a condenser made of either fused silica glass or fused borosilicate glass as specified in ISO 4797 and ISO 4799.
Use the following procedure:
a) Place a specimen weighing as much as its specific gravity in grams in the basket. Shake the basket gently and then place it in a weighing bottle with a lid and carefully weigh it.
b) Pour 80 ml of pure water [pH (7,0±0,5)] into the clean and dried flask coupled to a condenser. Then place the flask in the heating apparatus for 10 min.
c) Gently place the basket containing the specimen in the flask. After heating for 60 min in the apparatus, remove the basket.
d) Pour 80 ml of alcohol into a 100 ml beaker. Then soak the basket in the alcohol and rinse it.
e) After repeating operation d) three times, the basket shall be put in a weighing bottle and dried in an oven at the temperature between 120 °C and 130 °C for one hour.
f) Cool the weighing bottle for one hour in a desiccator with silica gel and weigh it carefully together with a lid.
The procedures described above, from a) to f), shall be repeated twice.
The percentage weight loss (%) is obtained from the initial weight of the specimen and the total weight.Two individual measurements are carried out to obtain the mean value.
The test report shall include the following information:
a) a reference to this document;
b) an identification of the samples;
c) a designation of the water resistance;
d) any unusual features noted during the determination.ISO 21575 pdf download.
