Visual testing (VT) is also known as visual testing examination, nondestructive inspection, or nondestructive evaluation or examination. Visual testing is the most common nondestructive testing method. Visual testing is a popular NDT method, because it is so easy to perform, it is a low-cost method, and it requires minimal equipment. VT involves observing a component with the naked eye to evaluate the presence of surface discontinuities. VT can be assisted with optical instruments such as magnifying glasses, boroscopes, mirrors, and other computer equipment for remote viewing. If a component can be viewed, visual testing is the first method of testing in an NDT examination. Visual testing can be performed on components that show visible corrosion or degradation such as welds, storage tanks, piping, boilers, and pressure vessels.
