ASTM E94

Covers — radiographic examination of welds and castings using industrial radiographic film: technique, source/energy selection, film and screens, IQI (penetrameter) use, exposure, processing, and viewing for volumetric flaw detection.

Does NOT cover (exclusions) — the following are governed elsewhere:

• Surface-only flaws → PT (E165) or MT (E709).
• Ultrasonic volumetric examination → UT (E213); computed/digital radiography → related ASTM E-series and Section V articles.
• Acceptance criteria → the construction code (via ASME Section V).

RT sees through the wall to internal flaws; it needs radiation control and two-sided access.

E94 sets guidance for radiographic examination:

• Technique & Source — X-ray or gamma source and energy selected for the material thickness.
• Image Quality — IQI/penetrameter to demonstrate required sensitivity and density.
• Geometry & Exposure — source-to-film distance, alignment, and exposure to control unsharpness.
• Processing & Interpretation — film development, viewing conditions, and record retention.

ASTM E94 guides radiographic examination (RT) using industrial film — a volumetric method that images internal discontinuities such as porosity, slag, lack of fusion, and through-wall cracks in welds and castings. Image quality indicators verify that the required sensitivity was achieved.

RT provides a permanent, interpretable record but requires radiation-safety controls and typically two-sided access. It is the traditional partner to ultrasonic testing for volumetric weld inspection; the construction code (via Section V) sets acceptance.

Engineering Note: Confirm the IQI/penetrameter sensitivity on every radiograph — an image that fails to resolve the required IQI hole/wire is not acceptable evidence, regardless of how clean the weld looks.