Laser Classification System According to IEC 60825-1 and ANSI Z136.1

Laser Classification Overview (Class 1 to Class 4)

Every commercial, industrial, research, and medical laser device is classified according to its potential biological hazard to the human eye and skin. LaserSafe computes exact AEL thresholds and measurement aperture conditions.

• Class 1 & Class 1M: Safe under reasonably foreseeable conditions. Class 1M poses ocular hazards if viewed with magnifying optical instruments.
• Class 2 & Class 2M: Visible lasers (400–700 nm) with output up to 1 mW where eye protection is afforded by natural aversion responses (blink reflex, 0.25 s).
• Class 3R & Class 3B: Medium-power lasers. Class 3R (up to 5 mW visible) represents low injury risk. Class 3B (up to 500 mW CW) is directly hazardous to the eye.
• Class 4: High-power lasers (> 500 mW) causing severe eye and skin injuries from direct beams and diffuse reflections, presenting significant fire hazard.

Accessible Emission Limits (AEL) & Correction Factors

Calculation of Accessible Emission Limits involves determining wavelength parameters, exposure durations (time base), source angular subtense (α), and thermal interaction times (Ti).