Classes of Lasers
Laser safety training is always recommended for all classes of lasers. It is required for Level 3B and 4 Lasers. Following the engineering controls and use practices outlined in the manufacturer's instructions is best practice for all lasers below Class 3B/4.
Class 1 and 1M lasers and laser systems are considered safe and incapable of producing damaging laser radiation levels during normal operation.
Example: CD/ DVD players
Class 1 and 1M lasers and laser systems are exempt from control under the Laser Safety Program.
Class 2/2M are low-powered lasers with an output of approximately 1 milliwatt (mW) of continuous wave. All class 2 lasers operate in the visible portion of the electromagnetic spectrum of 400–700 nanometers (nm).
Example: barcode scanners
Eye protection is usually afforded by aversion response and blink reflex (0.25 seconds). However, a class 2 laser beam could be hazardous if one were to intentionally expose the eye for longer than 0.25 seconds.
Class 2 and 2a lasers and laser systems are exempt from control under the Laser Safety Program.
Class 3 lasers and laser systems can emit any wavelength and may be hazardous under direct and specular viewing conditions, but diffuse reflection is usually not a hazard. These lasers are usually not a fire hazard.
Class 3 lasers and laser systems are exempt from control under the Laser Safety Program.
Class 3R lasers operate at 1–5 mW of continuous-wave.
Example: laser pointers
Class 3R lasers and laser systems are exempt from control under the Laser Safety Program.
- Best Practice: Do not view the direct or reflected beam.
Class 3B lasers operate at 5–500 mW of continuous-wave. Specific control measures are required to prevent direct or reflected beam viewing.
Principal investigators must meet these requirements for class 3B use:
- Register all class 3B lasers or laser systems with EH&S prior to use
- Complete the Laser SOP
- Complete and have all laser personnel complete Laser Safety Training in BioRAFT/SciShield
Class 4 lasers and laser systems operate at greater than 500 mW (continuous), can emit any wavelength, and are considered an eye, skin, fire, and diffuse reflection hazard. The most stringent control measures have been established for these lasers.
Specific control measures to prevent eye and skin exposure to direct and diffusely reflected beam are required.
Principal investigators must meet these requirements for class 4 use:
- Register all class 3B lasers or laser systems with EH&S prior to use
- Complete the Laser SOP
- Complete and have all laser personnel complete Laser Safety Training in BioRAFT/SciShield
Manufacturers are required by the U.S. Food and Drug Administration to label lasers with a hazard classification. In cases where the laser class is unknown (e.g., if a researcher fabricates a laser or laser system), contact the EH&S Laser Safety Officer at [email protected] to evaluate and classify the laser system.
