What is a visual inspection?

During a visual inspection an object is viewed and evaluated with the naked eye. It is a non-invasive method that does not involve the use of measuring equipment. Visual inspection is used, for example, to check the general condition and functionality of a piece of equipment. Visual inspections are used, among other things, in the areas of maintenance and quality inspection. Visual inspection has been standardized in DIN EN 13018 (General principles of visual inspection).

What does a visual inspection look like?

The visual inspection is usually performed by a qualified employee who has the necessary expertise to perform the inspection. During the visual inspection, the employee inspects the object thoroughly and looks for obvious signs of wear (cracks, deformation, corrosion, etc.) or damage. In doing so, the visual inspection is performed with the naked eye or with tools such as a flashlight or magnifying glass. The results of the visual inspection are usually documented in an inspection report.

What tools are available for a visual inspection?

In the DIN EN 13018 standard, one form of visual inspection is referred to as "direct visual inspection with aids". In this case, certain aids are used in the visual inspection to facilitate an assessment with the naked eye. Common aids are flashlights, magnifying glasses, mirrors and cameras.

What are typical defects discovered during a visual inspection?

Since visual inspection is performed with the naked eye, this form of inspection is not suitable for detecting all forms of defects. Visual inspection can detect obvious defects and damage in particular. Common defects that are detected include scratches, cracks, dirt deposits, color changes or assembly errors.

What is the difference between a direct and indirect visual inspection?

DIN EN 13018 distinguishes between direct and indirect visual inspection. In direct visual inspection, the employee inspects the object with the naked eye. Aids such as magnifying glasses or mirrors can be used. In indirect visual inspection, the respective object is not viewed directly by the employee's eye, but by a camera or videoscope.

What are the disadvantages of visual inspection?

Compared to other automated forms of testing, visual inspection has one key disadvantage. It is primarily performed by humans, which reduces the efficiency of the inspection compared to automated inspections. Due to overtiredness or lack of concentration, not all obvious defects may be detected by the employee.

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