What is required for the visual inspection of the test panel?

For the visual inspection of the test panel, having a removable back is important because it allows for thorough examination of the internal components and the conditions of the materials used. This accessibility ensures that inspectors can check for any defects, proper insulation, and adherence to safety and quality standards without compromising the integrity of the panel.

The ability to remove the back facilitates the assessment of the installation and any potential issues that may not be visible from the outside, which is crucial in confirming that the refractory has been applied correctly and is performing as expected. This level of inspection is vital for ensuring compliance with industry standards and ensuring the longevity and safety of the materials used.