Which option best describes a disadvantage of dry developer in relation to surface coating?

• A. Difficult to assure entire part surface has been coated
• B. Easily cleaned from surface after inspection
• C. High contrast background is formed for visible systems
• D. Very portable spray can

Answer: (A)

A sees the main issue as the difficulty of achieving full surface coverage with dry developer. Since this type uses a powder that must physically stick to the surface, deposition depends on gravity, airflow, and static adherence. Complex geometries, sharp edges, deep recesses, and curved surfaces make it easy for powder to miss areas, so some portions of the part may not be coated evenly or at all. If any region isn’t properly coated, penetrant drawn into defects won’t be brought to the surface reliably, reducing defect visibility and inspection sensitivity. The other statements describe properties that are advantages of dry developer (ease of removal after inspection, strong contrast, portability), not disadvantages related to coating completeness.