Hole size that must be visible in RT when using Hole-type IQI?

Hole size that must be visible in RT when using Hole-type IQI?

• A. 1T
• B. 2T
• C. 3T
• D. 4T

Answer: (B)

In radiographic testing with a hole-type IQI, the holes are sized in multiples of the material thickness (1T, 2T, 3T, 4T). The minimum requirement is that the 2T hole is clearly visible on the radiograph. This provides a practical measure of technique sensitivity: if you can see the 2T hole, the exposure and processing are adequate to reveal flaws at the corresponding thickness. The 1T hole is often too small to dependably discern, while 3T and 4T being visible simply indicate higher sensitivity but are not the required standard. So, the hole size that must be visible is the 2T hole.

In radiographic testing with a hole-type IQI, the holes are sized in multiples of the material thickness (1T, 2T, 3T, 4T). The minimum requirement is that the 2T hole is clearly visible on the radiograph. This provides a practical measure of technique sensitivity: if you can see the 2T hole, the exposure and processing are adequate to reveal flaws at the corresponding thickness. The 1T hole is often too small to dependably discern, while 3T and 4T being visible simply indicate higher sensitivity but are not the required standard. So, the hole size that must be visible is the 2T hole.