Direct visual examination of a pipe weld requires a minimum light intensity of how many footcandles?

Direct visual examination of a pipe weld requires a minimum light intensity of how many footcandles?

• A. 50
• B. 100
• C. 150
• D. 200

Answer: (B)

Direct visual examination relies on enough light to clearly reveal surface features such as cracks, porosity, undercut, or misalignment along the weld. Adequate illumination improves contrast and lets the inspector distinguish flaws from the shiny weld crown and base metal. The standard specifies a minimum of 100 footcandles on the surface to provide sufficient detail under typical shop or field conditions. At 100 footcandles (about 1076 lux), small defects become visible without excessive glare; lower lighting can obscure flaws, while much higher lighting isn’t necessary and can cause glare or fatigue. So, the minimum light intensity needed is 100 footcandles.

Direct visual examination relies on enough light to clearly reveal surface features such as cracks, porosity, undercut, or misalignment along the weld. Adequate illumination improves contrast and lets the inspector distinguish flaws from the shiny weld crown and base metal. The standard specifies a minimum of 100 footcandles on the surface to provide sufficient detail under typical shop or field conditions. At 100 footcandles (about 1076 lux), small defects become visible without excessive glare; lower lighting can obscure flaws, while much higher lighting isn’t necessary and can cause glare or fatigue. So, the minimum light intensity needed is 100 footcandles.