Betekenis en gebruik
4.1 Materials made from photodegradable plastics deteriorate rapidly when exposed to solar radiation, oxygen, warmte, 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, biologische aanvallen, en blootstelling aan zout water. 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. Daarom, 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. Echter, exposure to similar materials with known outdoor properties, controles, 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. Belangrijke factoren zijn onder meer de regeling van de lijnspanning, afwezigheid van zout- of andere waterafzettingen, temperatuur- en vochtigheidscontrole, and condition and age of burners and filters.

Opmerking 2: Voor aanvullende informatie over bronnen van variabiliteit en strategieën om variabiliteit in het ontwerp aan te pakken, executie, en data-analyse van versnelde blootstellingsproeven in laboratoria, 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:

Straal
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, en evaluatie van testresultaten.

1.2 Deze norm is niet bedoeld om alle veiligheidsproblemen aan te pakken, indien aanwezig, die verband houden met het gebruik ervan. Het is de verantwoordelijkheid van de gebruikers van deze norm om de juiste veiligheid te garanderen, gezondheids- en milieupraktijken en om vóór gebruik de toepasbaarheid van wettelijke beperkingen vast te stellen.

Opmerking 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 Deze internationale norm is gebaseerd op internationaal erkende standaardisatieprincipes die zijn vastgelegd in het Besluit over de beginselen voor de ontwikkeling van internationale normen, Richtlijnen en aanbevelingen uitgegeven door het WTO-comité voor technische handelsbelemmeringen.