Which shielding gas options meet GTAW-P requirements?

• A. Argon, Helium
• B. Argon only
• C. Oxygen, Argon
• D. Carbon Dioxide

Answer: (A)

Shielding gas in GTAW-P must protect the molten weld from air without introducing reactive elements. Noble gases like Argon and Helium are inert, so they don't react with the weld pool or tungsten arc. Argon is the standard shielding gas, and Helium is also acceptable—often used when more heat is needed or when welding thicker sections because Helium transfers more heat to the weld. So, both Argon and Helium meet GTAW-P shielding gas requirements.

Oxygen and Carbon Dioxide contain oxygen and will react with the molten metal, causing oxidation, porosity, and weaker welds, so they do not meet the requirements.