Class3a Class3b

Classification of laser devices

Categorized in the Separate Table of Classifications, laser devices are classified by the effect of the laser device upon the body, which is determined based upon the accessible emission limit. The accessible emission limit is calculated from the wavelength and emission period of the laser beam. The categories are defined as follows:

class 1 : Laser devices with lower output (less than about 0.39 μW) that pose no risk of injury to the body.
class 2 : Laser devices emitting visible light (wavelength: 400 to 700 nm) with an output that poses risk of injury that can be avoided by the defense reaction of human body (less than 1 mW).
class3A : Laser devices with an output not exceeding 5 times that of class 2 lasers (i.e., less than 5 mW). Exposure of the eye to Class 3A lasers is hazardous.

class3B :
Laser devices emitting laser beam with an output that poses risk of eye injury in cases of direct exposure to the laser beam or indirect exposure by the specular reflection. Laser devices emitting laser beam with an output that poses no risk of eye injury in case of exposure to the laser beam by the diffuse reflection (less than about 0.5 W).
class 4 : Laser devices emitting laser beam with an output that poses risk of eye injury in case of exposure to the laser beam (greater than about 0.5 W).
1W = 103mW = 106μW

Scope of application

The Measures apply to operations involving laser devices of classes 3A, 3B, and 4. However, the Measures shall not apply to laser operations for educational or research purposes within medical and educational research organizations.