Views:0 Author:Site Editor Publish Time: 2021-09-23 Origin:Site
In most cases, ISTA procedures and projects require at least one product package test, but a single "pass" cannot provide reliable confidence for other seemingly identical product packages to pass. This is due to packaging materials, packaging components, and packaging. The contents and other inherent statistical factors are affected. ISTA usually recommends repeating the test, each time a new sample is used. Successful testing of the same 3 packages helps to increase confidence. If possible, even if 5 or more samples are recommended, even if 10 packages successfully pass the test, there is no guarantee that all future tests will be successful.
There is no clear definition about the appropriate sample size, it may depend on the purpose of the test, the desired level of confidence, and the availability of the sample. The ISTA procedures and projects clarify the minimum number of samples required to pass ISTA to obtain package certification. In addition, ISTA usually encourages repeated testing. ISTA’s policy is that if any sample fails any test, the entire test will be considered a failure.
For larger sample sizes, additional testing time should not be an obstacle to better testing techniques. For example: Most vibration tests allow users to test multiple packages at the same time, which saves a considerable amount of time. In this way, the test time of 5 samples of the same size is basically the same as that of 1 sample.
Sometimes, the appropriate sample size cannot meet the minimum requirements of the test. In most cases, it is not allowed to use non-functional "simulation" products, but it is acceptable to use samples with minor identifiable damage (such as minor surface scratches). The key is whether the product is damaged according to the acceptance level of product damage determined before the start of the test after the test is completed. Another way is to use the product in multiple tested packages and perform appropriate inspections to ensure that the product has not been damaged. Users must be cautious when using products that are more prone to damage due to previous testing. In this way, 1 product and 3 packages can realize 3 product package test samples, test 3 times, and repackage a single usable product each time.