Whether the radiation of laser cutting machine will cause harm to human body
The laser of the laser cutting machine is a special energy light source. This type of laser is radiated to a certain extent, and how harmful is this radiation? According to the difference of laser light radiation, CDEH and IEC are generally Under the circumstances, the hazard levels of lasers and laser products are divided into four levels, and the basis of the classification corresponds to the treatable radiation limit AEL, that is, AEL is the maximum radiation allowed for each level of laser and laser products. AEL is related to the wavelength and the length of exposure time under radiation.
The first level: Under normal operating conditions, it will not produce light radiation that is harmful to people.
Second level: its radiation range is in the visible spectrum, and its AEL value is equivalent to the value when exposed to the radiation of the first level product for 0.25 seconds. This level of product requires additional warning signs for safety testing
The third level: divided into two levels of 3a and 3b. Level 3a will not cause damage to the naked eye for people who have a normal evasive response to strong light, but it will cause damage to the human eye for observation by using a lens instrument. Class 3b products include radiation in the range of 200nm to 1000000nm, which can cause accidental injury if the naked eye looks directly. Its management and control are stricter than the second level.
Fourth level: AEL is above the third level, which will not only cause damage to human eyes when looking directly, but also cause external damage in other situations. Not only to the eyes, but also to the skin and even cause fire. Strict management and control are required for this type of product.
According to the CDRH standard, for optical fiber communication systems using 1550nm lasers and single-mode fibers, the output power of the first-level products should be below 8.5mW, and the fourth level is greater than 500mW. According to the IEC standard, for optical fiber communication systems using 1550nm lasers and single-mode fibers, the output power of the first-level products should be below 10mW, less than 50mW is the third level, and more than 500mW is the fourth level.
After the introduction of fiber amplifiers in optical communication systems, because the output power of fiber amplifiers is greater than that of general semiconductor lasers, as a type of laser product, the radiation safety used by them has also attracted everyone's attention. In formulating standards for optical communication systems, especially systems that use fiber amplifiers (such as wavelength division multiplexing), the ITU (T-ITU) has also taken into account the safe use of lasers. Some recommendations such as G.691 and G. 692, G.664, G.957, etc., have introduced the relevant definitions and descriptions of IEC825.
The laser cutting machine is different from other ordinary light sources. The laser produced by the laser can achieve the effect of energy concentration due to its monochromaticity, coherence, collimation and high energy density, thereby causing damage to human organs (especially the human eye). . For the laser in the infrared region, the damage to the human body is mainly the thermal effect, and for the laser in the blue and violet regions, the damage is mainly the photochemical effect. Therefore, when the human eye accidentally directly faces the laser light emitted from the laser or the fiber connector, it may cause damage to the eyes. If it is an ultraviolet laser, it may cause corneal inflammation and cataracts. For the currently used 1550nm laser, the light source of the laser marking machine is in the far infrared band, which mainly causes damage to the cornea and eye lens
