What kind of penetrant can be used under ordinary shop light?

• A. Visible color contrast penetrants
• B. Fluorescent penetrants
• C. Magnetic particle penetrants
• D. Liquid penetrants that require UV illumination

Answer: (A)

Visible color contrast penetrants are designed to be seen under normal lighting. After the penetrant seeps into surface flaws and excess is removed, a developer draws the dye to the surface, creating a colored indication that stands out in ordinary shop light. This makes flaw detection practical without UV equipment. Fluorescent penetrants, while more sensitive, need UV illumination to glow, so they aren’t visible under normal lighting. Magnetic particle methods involve a different testing approach and aren’t the same type of penetrant indication. Therefore, the penetrant that works with ordinary shop light is the visible color contrast type.