Methods of applying dry developers?

• A. Electrostatic spraying
• B. All of the above
• C. Immersion
• D. Air suspension (storm chamber)

Answer: (B)

Dry developer must be deposited evenly on the surface so that any penetrant retained in flaws becomes visible. One effective method uses electrostatic spraying: the powder is charged and attracted to the surface, giving a uniform coat even on complex shapes and recessed areas. Immersion here refers to exposing the part to a dry developer bed or chamber where the powder surrounds the part, coating surfaces in a controlled way—useful for small parts or features that are hard to reach. The air suspension or storm chamber method blasts or suspends dry developer powder in a stream of air while the part moves through, coating large or irregular surfaces quickly and uniformly. Because each method offers reliable, surface-covering deposition under different part geometries and production speeds, all of these approaches are valid ways to apply dry developer.