This standard specifies procedures for accelerated exposure testing of coatings using an unfiltrated open fire carbon arc device, including the preparation of the specimen and the choice of test conditions. Its main purpose is to assess the performance degradation of coatings in an accelerated environment simulating sunlight, moisture and heat. During the test, the radiation characteristics produced by an unfiltrated open fire carbon arc are significantly different from those of a Miscellaneous Light source and may therefore lead to different types and rates of degradation. To ensure the accuracy and Repeatability of the results, experiments are performed under the same exposure conditions and the results are recorded in detail and statistically analyzed.