Laser cutter’s laser is a special kind of energy source, this type of laser is radiated at a certain extent, and how much harm of this radiation is there?
Depending on the laser irradiation, usually, CDRH and IEC divide the harm of laser and laser products into four grades, the classification in accordance with processable radiation limit AEL (AEL refer to allowable maximum radiation of laser in each level and laser products).
AEL has a relationship with the wavelength and time of exposure under radiation.
In normal operating conditions, there is no radiation that is harmful to humans.
The range of its radiation is in the visible spectrum region, and its AEL value is equivalent to the value of 0.25 seconds in radiation exposure to the first stage product.
The product needs additional warning marks for safety testing.
It’s divided into 3a and 3b level.
For the people who have normal avoidance response to the hard light, the 3a level will not cause harm to the naked eye, but in the case of observing through the use of the lens instrument, it will cause harm to people’s eyes.
3b level including radiation from 200nm to 1000000nm. Look in naked eyes can cause accidental damage.
The management and control of it are stricter than the second level.
Above the third level, not only hurts the human eyes when looking directly, but also cause injury in other situations, such as the skin, or even cause fire.
Strict management and control of this kind of products should be carried out.
According to the CDRH standard, the output power of the first level product should be below 8.5mW for laser device and the single-mode optical fiber communication system which using a 1550nm laser. If the power is higher than 500mW, then it belongs to the 4th level.
According to IEC standard, the output power of the first stage product should be below 10mW for the laser device and single-mode optical fiber communication system which using a 1550nm laser. If the power is less than 50mW, it belongs to 3rd level. If greater than 500mW, it is the 4th level.
After the introduction of optical fiber amplifier in an optical communication system, as a kind of laser products, the radiation safety getting a lot of attention as a result of the output power of the optical fiber amplifier is greater than the general semiconductor lasers.
When International Telecommunications Union (ITU-T) making the standard for the optical communication system, especially the use of optical fiber amplifier systems (such as WDM), they take into consideration the safe use of lasers. In some suggestions such as G. 691, G. 692, G. 664, G. 957 etc, IEC825 related definition and description are introduced.
The light of the laser cutting machine is different from other ordinary light. The laser generated by the laser source is monochromatic, coherence, collimation and high-density energy, therefore it can achieve the effect of energy concentration, and cause harms to the human organs (especially the eyes).
For the laser in the infrared spectrum region, the damage to the human body is mainly the thermal effect, and the laser in the blue and ultraviolet spectrum is mainly photochemical.
Therefore, when the human eye is directly exposed to a laser from a laser source or optical fiber connector, it can cause damage to the eye.
If it is an ultraviolet laser, it can lead to inflammation of the cornea and cataract.
For the current laser source using a 1550nm laser, the light source of the laser marking machine is in the far infrared band, which mainly causes the damage to the cornea and the lens of the eye.