: Also known as "candling," this involves using artificial light to shine through translucent materials (like laminates) to detect thickness variations or subsurface flaws. 3. Critical Variables and Equipment Illumination : A minimum light intensity of 100 footcandles (1000 lux)
If you are inspecting a 20-year-old vessel for corrosion, you use the tools of Article 9, but the rules of the repair code (NBIC or API). asme section v article 9
: All visual examinations must follow a detailed written procedure. : Also known as "candling," this involves using