Welding Lens Shade — What It Is and Why It Matters
Welding lens shade numbers indicate the darkness level of a welding filter lens, which protects the welder's eyes from the intense ultraviolet, visible, and infrared radiation produced by the welding arc. Higher shade numbers mean darker lenses that block more radiation.
The shade number system runs from shade 1 (lightest, for gas welding and cutting observation) to shade 14 (darkest, for extremely high-amperage processes). Each shade number roughly halves the amount of light transmitted. ANSI Z87.1 and AWS F2.2 provide recommended shade numbers based on welding process and amperage.
Choosing the correct shade is important: too light a shade causes eye strain, discomfort, and potential arc flash injury; too dark a shade makes it impossible to see the weld pool clearly, causing technique problems. Most MIG and stick welding falls in the shade 10-12 range. TIG welding at lower amperages may use shade 8-10. Always err on the side of a darker shade if uncertain.
Frequently Asked Questions
What shade do I need for MIG welding?
For MIG welding at 60-160 amps, shade 10 is standard. At 160-250 amps, shade 11-12. Above 250 amps, shade 12-13. These are guidelines — adjust based on comfort. If you see the weld pool clearly and your eyes feel comfortable after extended welding, the shade is right.
Can the wrong shade damage my eyes?
Yes. Too light a shade allows excessive UV and visible light to reach your eyes, causing arc eye (photokeratitis) — a painful condition similar to sunburn on the cornea. Even brief exposure to an unprotected arc can cause arc eye symptoms. Always verify your shade is appropriate before welding.