What lens shade is recommended for most oxy-fuel cutting applications?

• A. 3
• B. 5
• C. 8
• D. 10

Answer: (B)

Choosing the lens shade for oxy-fuel cutting is about balancing eye protection with visibility. The flame from acetylene-oxygen cutting is very bright and emits strong UV and IR radiation, so the lens needs to be dark enough to protect the eyes. A mid-range shade of 5 provides sufficient protection for the typical brightness of the cutting flame while still letting you clearly see the cut line, edges, and alignment marks. Shades that are too light won’t shield your eyes adequately from the radiant energy, increasing the risk of eye injury. Shades that are too dark make it hard to see the work, slowing you down and reducing precision. For most cutting tasks, shade 5 hits the right balance, though more demanding or different setups might call for adjustments.