Laser Safety Program: Laser Hazard Classifications
Read about laser hazard classifications and requirements used in UC San Diego's Laser Safety Program.
Laser hazard classification is based on the ability of the primary laser beam to cause biological damage to the eye or skin during intended use. UC San Diego researchers must determine the hazard classification of each laser or laser system they obtain or fabricate.
The UC San Diego Laser Safety Program adheres to the American National Standards Institute (ANSI) Z136.1-2007 system of classifying continuous–wave (CW) lasers and single-pulse lasers according to their relative hazards.
Controls required by the Laser Safety Program are determined by the hazard classification of a laser or laser system and how and where it will be used.
Follow the Laser Safety Program requirements below specified by hazard class:
Class 1 and 1M
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.
- Best practices:
- Follow general engineering control measures described on Laser Hazard Control Measures.
- Laser safety training is recommended for personnel working with class 1M lasers or laser systems.
Class 2 and 2M
Class 2 and 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.
- Best practices:
- Follow general engineering control measures described on Laser Hazard Control Measures.
- Laser safety training is recommended for personnel working with class 2 and 2M lasers or laser systems.
Class 3
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.
- Best practice:
- Follow general engineering control measures described on Laser Hazard Control Measures.
Class 3R
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.
- Follow general engineering control measures described on Laser Hazard Control Measures.
Class 3B
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:
- Obtain Laser Use Authorization (LUA) prior to use.
- See Laser Use Authorization for details.
- Provide and document laser safety training for personnel using class 3B laser equipment.
- See Requirements for Class 3B and 4 Lasers for details.
- Provide and document medical surveillance for personnel using class 3B laser equipment.
- See Requirements for Class 3B and 4 Lasers for details.
- Register all class 3B lasers or laser systems with EH&S.
- Follow class 3B control measures described on Laser Hazard Control Measures, in addition to general engineering control measures.
Class 4
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:
- Obtain Laser Use Authorization (LUA) prior to use.
- See Laser Use Authorization for details.
- Provide and document laser safety training for personnel using class 4 laser equipment.
- See Requirements for Class 3B and 4 Lasers for details.
- Provide and document medical surveillance for personnel using class 4 laser equipment.
- See Requirements for Class 3B and 4 Lasers for details.
- Register all class 4 lasers or laser systems with EH&S.
- Follow class 4 control measures described on Laser Hazard Control Measures, in addition to general engineering control measures.
Class to be determined
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), do the following:
- Contact the EH&S Laser Safety Officer, (858) 822-2850, to evaluate and classify the laser system.