The safety classes of laser are ordered by increasing power, with lower power classes requiring lasers equipped with a warning label and higher power classes requiring warning labels and laser goggles. The ANSI Z136.1 classification of laser systems was updated in 2012 and is also listed below.
The ANSI Z136.1 laser system is a classification system for permanent laser sources. It uses MPE tables based on appropriate distance from the eye, such as the calculators used in ANSI Z136.1 Table 3-3 for MPEs. The ANSI Z136.1 system is more restrictive than the listed international classification, such as IEC 60825 for the range of laser power levels of visible and near infrared lasers.
Laser classification falls into five classes, with the thresholds of power and wavelength corresponding to the conditions required for injury to the eye with a direct-beam hit. Write-ups for each class are provided below.
Class 1 is for "weak" lasers; the threshold for injury is 50 mW at 532 nm, or about 3 mW at i region (810 nm). A class 1 laser operating at 1 W will provide about 5,000 times the threshold power. The power in this case must be listed, and the user must wear a safety helmet unless protected by the helmet requirement of the particular laser application. Wavelength class 1 requires no specific safety action from a laser for eyes or skin of a person wearing protective eyewear. The label is a single word with a triangular warning symbol to indicate that the laser will produce a direct beam that can cause harm. d2c66b5586