Green Laser Pointer Safety
Class, NOHD and dazzle distances of a laser pointer: its IEC 60825-1:2014 class, the nominal ocular hazard distance on the ICNIRP 2013 limits, and how far it causes flash-blindness, glare and distraction (ICAO levels).
Educational only — not compliance-grade
These pages implement the published exposure limits for the cases each one states, but they are educational tools: no laser safety officer has signed them off.
- Do not use these results alone for PPE selection, NHZ / NOHD approval, controlled-area sign-off, enclosure/interlock approval, or formal classification.
- Always verify against ANSI Z136.1, IEC 60825-1, your local procedures, and the responsible laser safety officer / CLSO.
Class (IEC 60825-1:2014)
Class 3R
Class 2 up to 1 mW, 3R up to 5 mW, 3B up to 0.5 W (visible CW)
NOHD (eye exposure 0.25 s)
16.4 m
Retina, thermal
At 10.0 m
5.40 mW/cm² over 7 mm
beam 13.5 mm; 2.08 mW into a 7 mm pupil
Flash-blindness (100 µW/cm²) out to
92.8 m
Glare (5 µW/cm²) out to
419 m
Distraction (50 nW/cm²) out to
4.20 km
Peak irradiance at 10.0 m: 6986 µW/cm².
Peak irradiance of the beam against distance (log scales) and the ICAO levels for flash-blindness, glare and distraction.
Class: a visible CW pointer is Class 2 up to 1 mW (the blink reflex limits the exposure to 0.25 s), Class 3R up to 5 mW and Class 3B up to 0.5 W, measured through a 7 mm stop 100 mm from the beam and a 50 mm stop at 2 m for binoculars (IEC 60825-1:2014). Many countries allow only Class 1 or 2 pointers for sale.
NOHD: the distance beyond which the beam stays within the ICNIRP 2013 eye limit for 0.25 s, averaged over 7 mm, with the beam spreading as d + rφ (the standards' formula). Dazzle: the beam blinds and dazzles far beyond the NOHD. The distances are where its peak irradiance falls to the ICAO flight-zone levels (Annex 11, Doc 9815): 100 µW/cm² (flash-blindness unlikely), 5 µW/cm² (glare unlikely), 50 nW/cm² (visual disruption unlikely). The FAA also weights the irradiance by the eye's sensitivity; not done here.
Not modelled: the infrared that cheap DPSS pointers can leak (808 and 1064 nm, often unfiltered, which can raise the class), atmospheric loss and scintillation.
Model and references
Textbook approximation. A standard approximation from the literature (for example paraxial, plane-wave or Gaussian-beam), valid within the range the page states. About the tiers
Class: IEC 60825-1:2014 CW AELs. NOHD: ICNIRP 2013, 0.25 s if visible (else 10 s), beam d + rφ. Dazzle: peak irradiance vs the ICAO levels, not weighted by eye sensitivity. Not modelled: IR leakage, atmosphere.
- IEC 60825-1:2014. Safety of laser products – Part 1: Equipment classification and requirements. Tables 3–8 (AELs), Table 10 (measurement conditions). webstore.iec.ch
- ICNIRP (2013). Guidelines on limits of exposure to laser radiation of wavelengths between 180 nm and 1,000 µm. Health Phys. 105(3), 271–295. Tables 5 and 8. doi:10.1097/HP.0b013e3182983fd4
- ICAO (2003). Doc 9815, Manual on Laser Emitters and Flight Safety; Annex 11. Laser-beam free (50 nW/cm²), critical (5 µW/cm²) and sensitive (100 µW/cm²) flight zones.