Earlier editions of Section V contained more descriptive text that has been streamlined in later editions. For example, specific wording about viewing distance and illumination sometimes varies between editions. However, the technical requirements are equivalent and maintained through cross-references.
ASME Section V (including Article 9) is available from:
The standard requires a minimum light intensity at the examination surface.
These limits ensure that the inspector maintains adequate resolution and perspective to detect fine defects like micro-cracks or undercut. Illumination (Lighting) Requirements asme section v article 9
A decrease in the minimum light intensity at the examination surface.
Older editions are sometimes available through public archives (e.g., the 2001 edition on Archive.org), but users should always refer to the latest applicable edition mandated by their project or jurisdiction.
Uses boroscopes, fiberscopes, videoscopes, cameras, or robotic crawlers. Earlier editions of Section V contained more descriptive
The scope of Article 9 is clearly defined in Paragraph T-910. Specific visual examination procedures required for every type of examination are not included in this Article, because there are many applications where visual examinations are required. Examples of these applications include nondestructive examinations, leak testing, in-service examinations, and fabrication procedures.
is the section of the Boiler and Pressure Vessel Code (BPVC) dedicated to Nondestructive Examination (NDE) . Article 9 specifically addresses the requirements for Visual Examination (VT) .
Post heat treatment
Defects cannot be found in the dark. Article 9 sets explicit minimum light intensities measured at the examination surface:
Article 9 requires a at the examination surface for direct visual inspection. For critical welds or when detecting small discontinuities, 1,500–2,000 lux is standard practice. Lighting shall be white, non-glaring, and directed at a suitable angle to reveal surface defects.