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Three new samples (lenses) shall be subjected to five cycles of temperature
and humidity (RH = relative humidity) change in accordance with the
following programme:
3 hours at 40 °C ± 2 °C and 85-95 per cent RH;
1 hour at 23 °C ± 5 °C and 60-75 per cent RH;
15 hours at –30 °C ± 2 °C;
1 hour at 23 °C ± 5 °C and 60-75 per cent RH;
3 hours at 80 °C ± 2 °C;
1 hour at 23 °C ± 5 °C and 60-75 per cent RH;
Before this test, the samples shall be kept at 23 °C ± 5 °C and 60-75 per cent
RH for at least four hours.
Note: The periods of one hour at 23 °C ± 5 °C shall include the periods of
transition from one temperature to another which are needed in order to avoid
thermal shock effects.
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