Význam a použití
4.1 Materials made from photodegradable plastics deteriorate rapidly when exposed to solar radiation, kyslík, heat, moisture and other weather-degrading elements. This practice is used to assess the photodegradability of plastics when exposed to devices that produce simulated daylight (1,2) 6 and control temperature and humidity. The exposures used in this practice are not intended to simulate deterioration caused by local weather phenomena such as atmospheric pollution, biological attacks, and salt water exposure. Positive correlation of exposure results between this device and other laboratory aging devices is not possible.

4.2 Changes in results can be expected when operating conditions vary within the accepted limits of this practice. Proto, all test results using this specification need to be accompanied by the specific operating conditions required in Section 9. For more information about the precautions that apply to using results obtained under this practice, see Practice G151.

4.3 The results of laboratory exposure cannot be directly extrapolated to estimate the absolute rate of environmental degradation, as the acceleration factor depends on the material and can vary greatly for each material and different formulations of the same material. nicméně, exposure to similar materials with known outdoor properties, řízení, and simultaneously with test samples allows comparison of durability under test conditions relative to controls. The evaluation of relative durability also greatly improves the consistency of test results between different laboratories (3).

4.4 Test results will depend on the degree of care taken to operate the equipment in accordance with practice G155. Important factors include regulation of line voltage, absence of salt or other water deposits, temperature and humidity control, and condition and age of burners and filters.

Poznámka 2: For additional information on sources of variability and strategies to address variability in the design, execution, and data analysis of laboratory accelerated exposure trials, see Guideline G141.

4.5 Before continuing this practice, it is common practice to refer to the specifications of the material under test. Any sample preparation, adjustment, sizing, or test parameter or combination thereof covered in the Material Specification shall take precedence over the sample preparation, adjustment, sizing, or test parameter or combination thereof referred to in this specification. If there is no material specification, default conditions apply.

ASTM D5071-2022 Standard Test Method for Exposure Testing of Photodegradable Plastics in Xenon Lamp Devices:

Poloměr
1.1 This procedure covers specific procedures and test conditions applicable to xenon arc exposure of photodegradable plastics in accordance with practices G151 and G155. The practice also includes the preparation of samples, suitable test conditions for photodegradable plastics, and evaluation of test results.

1.2 Tato norma není určena k řešení všech bezpečnostních problémů, jestli nějaký, spojené s jeho užíváním. Je odpovědností uživatelů této normy zajistit odpovídající bezpečnost, zdravotní a environmentální postupy a určit použitelnost regulačních omezení před použitím.

Poznámka 1: This practice is technically equivalent to ISO 4892-2 and Practice D2565, which covers xenon arc exposure of long-term plastics for outdoor applications.

1.3 Tato mezinárodní norma je založena na mezinárodně uznávaných zásadách normalizace stanovených v Rozhodnutí o zásadách pro vývoj mezinárodních norem, Směrnice a doporučení vydané Výborem WTO pro technické překážky obchodu.