What is an incorrect use of crack panels (blocks)?

Crack panels, often referred to as blocks, are typically used in non-destructive testing (NDT) to simulate flaws and assess the performance of inspection techniques and penetrants. Each option presented considers a different aspect of their application in testing environments.

Establishing a standard size of a crack is not a primary use of crack panels. Typically, crack panels are designed with various artificial flaws to provide reference points for testing and ensuring equipment sensitivity, along with calibrating testing procedures.

Testing the sensitivity of penetrants involves applying the penetrants to these panels and observing how well they can detect the cracks, which makes this use suitable. Similarly, calibrating inspection equipment involves utilizing known flaws, such as those created in crack panels, to ensure that the equipment is functioning accurately within defined parameters. Preparing test specimens is also a common practice associated with NDT, where panels are used to create a controlled environment for testing.

In conclusion, while crack panels can be used to verify and assess many aspects of inspection techniques, establishing a standard size of crack is not one of their intended uses, making this option incorrect.