Which class is typically used for industrial cutting and is hazardous to view under any condition?

• A. Class 1
• B. Class 2
• C. Class 3B
• D. Class 4

Answer: (D)

Class 4 lasers are the highest-risk category and are the type used for industrial cutting. They deliver enough power to burn tissue and ignite materials, and any viewing of the beam—direct or reflected—can cause serious eye injury. That’s why they’re considered hazardous to view under any condition and require full containment, interlocks, and protective measures. Lower classes are designed to be safe under normal use and don’t carry the same all-around viewing and fire hazards that come with heavy industrial cutting beams.