ASNT Level III- Visual & Optical Testing

Marking materials used on austenitic stainless steels typically have a certified
analysis that meets the following specified maximum amounts of detrimental
contaminants:
1. inorganic halogen content less than 200 ppm by weight;
2. halogen (inorganic and organic) content less than 1 percent by weight;
3. sulfur content less than 1 percent by weight (measured in accordance with
ASTM D129); and
4. total content of low melting point metal (lead, bismuth, zinc, mercury,
antimony and tin) less than 200 ppm by weight and no individual metal
content greater than 50 ppm by weight.
The certification typically indicates the methods and accuracy of analysis and
the name of the testing laboratory.
Charlie Chong/ Fion Zhang