How does electrode contamination occur in GTAW, and what steps prevent it?

• A. Weld copper using oil-based cleaners.
• B. Contamination from oils, moisture, or touching the tungsten with bare skin; prevent by handling with clean gloves, avoiding skin contact, storing electrodes properly; grind away contaminated tips.
• C. Contamination from gas leaks.
• D. Contamination from incorrect filler metal grade.

Answer: (B)