What are the safety levels of lasers?

Lasers are divided into four safety levels. Different levels cause different hazards to the human body, and the protection standards for lasers are also different.

1. Security level: level one.
Laser power: less than 0.5 milliwatts, safe laser, first-class laser will not harm human health under normal use conditions, but this kind of product still needs to ensure that it is used to prevent workers from entering the laser radiation area during work Design.

2. Security level: Level two.
Laser power: 1 milliwatt. This level of laser has low-power, visible laser. Humans can protect themselves by blinking and reflecting the strong light. But looking directly for too long will bring danger. The second-level laser must be at the laser exit port. Warning signs are partially posted.

3. Security level: level three.
Level three is divided into two types, 3a and 3b. Level 3a laser, laser power: 1 mW to 5 mW. Level 3a laser is the same as level 2 and a warning sign must be posted at the laser exit. If it is only seen for a short time, the human eye will have a certain protective effect on the protective reflection of light, but if the light spot enters the human eye when it is focused, it will cause damage to the human eye.
Class 3b laser, laser power: 5 milliwatts. Up to 500 milliwatts, it may cause injury if you look directly or diffusely reflect. Class 3b lasers are generally affixed with "danger" signs. Although they are harmful to the eyes, if the light spot is not focused, there is less danger of causing fire or burns to the skin. However, it is recommended to wear eye protection when using this class of lasers.

4. Security level: level four.

Laser power: 500 milliwatts or more, this level of laser has great damage to the eyes and skin, direct reflection and diffuse reflection can cause damage. All Class 4 laser equipment must bear the "Danger" sign. Level 4 lasers can also damage materials near the laser and ignite flammable substances. When using this level of lasers, it is also necessary to wear eye protection devices like Level 3b.