المعنى والاستخدام
5.1 يقوم الجهاز بتعريض العينة للضوء, الحرارة والرطوبة الاختيارية, typically attempting to replicate the changes in specimen characteristics observed in both outdoor and indoor end-use environments. Exposure is not intended to simulate deterioration caused by local weather phenomena such as atmospheric pollution, biological attacks, and salt water exposure.

5.2 This practice allows for a wide range of exposure conditions that may produce significantly different results. لذلك, the results of its use should not be referred to unless accompanied by a report in section 10 detailing specific operating conditions.

5.2.1 Controls (similar materials with known properties) should be exposed at the same time as the sample to provide a reference for comparison purposes. It is better to use two different control materials: one known to have relatively poor durability and the other known to have relatively good durability. Each sample and control material should be repeated at least three times at the same time for statistical evaluation of the results.

ممارسة ASTM G155-2021 لمعدات مصابيح قوس الزينون للتعرض للمواد غير المعدنية

5.3 Results obtained from specimens exposed in different devices (even if the device is of the same model) using the same set point and operational controls should not be compared unless repeatability of the material to be tested has been established between devices.

5.4 Please refer to Practice G151 for warning guidelines applicable to all laboratory aging equipment.

5.5 Users are advised to follow good laboratory practices to reduce exposure variability (1). 8

نصف القطر
1.1 This practice is limited to the basic principles and procedures for operating xenon arc lamps and water installations; By itself, it does not provide specific results.

1.2 It is intended to be used in conjunction with practices or methods that define specific exposure conditions for applications and methods for assessing changes in material properties. This practice aims to reproduce the weathering effects that occur when materials are exposed to sunlight (directly or through window glass) and moisture (such as humidity, مطر, or dew) during actual use. This practice is limited to procedures for obtaining, measuring, and controlling exposure conditions.

ممارسة ASTM G155-2021 لمعدات مصابيح قوس الزينون للتعرض للمواد غير المعدنية

ملحوظة 1: A number of exposure procedures are listed in the appendix; لكن, this practice does not specify the appropriate exposure conditions for the material to be tested.

ملحوظة 2: Practice G151 describes the general procedures and performance requirements used when exposing materials in equipment that uses laboratory light sources.

1.3 Under controlled environmental conditions, the sample is exposed to light from an optically filtered xenon arc lamp. The combinations of different types of filters and xenon arc sources are described.

1.4 Sample preparation and result evaluation are covered in ASTM methods or specifications for specific materials. General guidance is given in Practice G151.

ملحوظة 3: General information on methods for determining post-exposure changes in properties and reporting these results is described in Practice D5870.

1.5 لا تنطبق هذه الممارسة على اختبار تآكل المعادن العارية.

1.6 الوحدات – يجب اعتبار القيم المعبر عنها بوحدات النظام الدولي (SI) قيمًا قياسية. ولا يتم تضمين أي وحدات قياس أخرى في هذا المعيار.

1.7 This practice is technically similar to the following ISO documents: ايزو 4892-2, ايزو 16474-2, ISO 105-B02, ISO 105-B04, ISO 105-B05, ISO 105-B06 and ISO 105-B10.

ممارسة ASTM G155-2021 لمعدات مصابيح قوس الزينون للتعرض للمواد غير المعدنية

1.8 لا يهدف هذا المعيار إلى معالجة جميع المخاوف المتعلقة بالسلامة, لو اي, المرتبطة باستخدامه. تقع على عاتق مستخدمي هذه المواصفة القياسية مسؤولية تحديد السلامة المناسبة, الممارسات الصحية والبيئية وتحديد إمكانية تطبيق القيود التنظيمية قبل الاستخدام.

1.8.1 If the operation of the lamp produces any ozone, it should be removed from the sample and the operator through the exhaust system.

1.9 يعتمد هذا المعيار الدولي على مبادئ التقييس المعترف بها دوليًا المنصوص عليها في القرار المتعلق بمبادئ تطوير المعايير الدولية, المبادئ التوجيهية والتوصيات الصادرة عن لجنة منظمة التجارة العالمية المعنية بالحواجز الفنية أمام التجارة.