Kahulugan at paggamit
4.1 Ang medyo mabilis na pagkasira ng kemikal, physical and mechanical properties of materials made from photodegradable plastics when exposed to light, heat and water after achieving their intended purpose. This practice is designed to cause changes in properties related to the conditions the material may encounter when discarded as garbage, including the effects of sunlight, moisture, and heat. 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.

4.2 Precautions – When operating conditions vary within the acceptable limits of this practice, results can be expected to change. Kaya nga, reference to the use of this practice must not be made unless accompanied by a report prepared in accordance with section 9 describing the specific operating conditions used. For more information about the precautions that apply to using results obtained under this practice, see Practice G151.

Tala 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.

ASTM D5208-2022 Standard Practice para sa Fluorescent Ultraviolet Rays

4.3 Simultaneous exposure to similar materials with known properties (mga kontrol) with the sample provides criteria for comparison purposes. The use of controls to rank the stability of test materials greatly improves consistency across different laboratories. It is recommended that at least three repetitions of the material for each evaluation be performed in order to statistically evaluate the results.

4.4 Test results will depend on the degree of care taken to operate the equipment in accordance with practice G154. Important factors include regulation of the line voltage, the temperature of the room in which the equipment is operating, temperature control, and the condition and age of the lamp (if exposed in equipment without irradiance control).

Radius
1.1 This procedure covers specific procedures applicable to fluorescent ultraviolet (UV) irradiation of photodegradable plastics in accordance with procedures G151 and G154. The practice also includes the preparation of test samples and the evaluation of test results.

1.2 Practice D4329 covers fluorescent UV exposure to plastics used for outdoor applications.

ASTM D5208-2022 Standard Practice para sa Fluorescent Ultraviolet Rays

1.3 Values expressed in SI units shall be treated as standard values. Ang mga halaga na ibinigay sa mga panaklong ay para sa sanggunian lamang.

1.4 Ang pamantayang ito ay hindi nilayon upang matugunan ang lahat ng mga alalahanin sa kaligtasan, kung meron man, na nauugnay sa paggamit nito. Responsibilidad ng mga gumagamit ng pamantayang ito na magtatag ng angkop na kaligtasan, mga kasanayan sa kalusugan at kapaligiran at upang matukoy ang pagiging angkop ng mga paghihigpit sa regulasyon bago gamitin.

Tala 1: There is no known ISO equivalent to this standard.

1.5 Ang internasyonal na pamantayang ito ay batay sa mga prinsipyo ng standardisasyon na kinikilala ng internasyonal na itinatag sa Desisyon sa mga Prinsipyo para sa Pag unlad ng mga Internasyonal na Pamantayan, Mga Patnubay at Rekomendasyon na inilabas ng WTO Committee on Technical Barriers to Trade.