The Show Laser Light Guide - Laser classes

Laser systems are classified in several levels, according to their accessible radiation. The classification is meant to indicate the hazard level of laser system. Show laser light systems can be of class 2, 2M, 3R, 3B or 4 (in the order of their hazardousness). Laser class 2 classifies very small and weak laser devices with an output power of <1mW. Laser systems with an output power between 1mW and 5mW are rated class 3R, between 5mW and 500mW are rated class 3B. Every laser with more than 500mW accessible radiation is specified class 4.
Even class 4 lasers are safe for audience scanning, if the MPE is not exceeded in the audience area. 

Remember to always respect local regulations and laws when operating a laser system

Find further information here:

In the Laser FAQ:
- Laser Classes - specifications

In the Laser Glossary:
- MPE - Maximum Permissible Exposure
- AR - Accessible Radiation