Which shade range is not listed for oxy-fuel welding in the material?

• A. 4 to 8
• B. 6 to 14
• C. 7 to 14
• D. 9 to 12

Answer: (D)

Shade numbers indicate how dark the protective visor should be to guard against the flame and radiant light. Oxy-fuel welding relies on a flame rather than an electric arc, so the protection needed is less intense and the commonly listed ranges for oxy-fuel fall in the mid-light to mid-dark spectrum. The range of 9 to 12 is typically associated with protecting against an electric arc, not a flame, so it isn’t listed for oxy-fuel welding in the material.