What is the radiography joint efficiency for full radiography?

• A. 0.85
• B. 0.70
• C. 0.95
• D. 1.00

Answer: (D)

The key idea here is that joint efficiency represents how much of the weld is effectively examined by the nondestructive test. When full radiography is used, the entire weld is inspected, so the detection capability applies to the whole joint. That makes the joint efficiency unity, or 100%. In other words, there’s no reduction in effective weld strength due to nondestructive testing when the weld is fully radiographed.

The other values would correspond to partial radiography or different testing coverage, where only a portion of the weld is inspected and some reduction in reliability is assumed.