Possible dangers caused by using lasers: laser radiation damage, electrical damage, mechanical damage, dust gas damage.

1.1 Laser class definition
Class 1: Safe within the device. Usually this is because the beam is completely enclosed, such as in a CD player.

Class 1M (Class 1M): Safe within the device. But there are dangers when focused through a magnifying glass or microscope.

Class 2 (Class 2): It is safe under normal use conditions. Visible light with a wavelength of 400-700nm and the eye’s blink reflex (response time 0.25S) can avoid injury. Such devices typically have less than 1mW power, such as laser pointers.

Class 2M: Safe within the device. But there are dangers when focused through a magnifying glass or microscope.

Class 3R (Class 3R): The power usually reaches 5mW, and there is a small risk of eye damage during the blink reflex time. Staring at such a beam for several seconds can cause immediate damage to the retina.​

Class 3B: Exposure to laser radiation can cause immediate damage to the eyes.

Class 4: Laser can burn skin, and in some cases, even scattered laser light can cause eye and skin damage. Cause fire or explosion. Many industrial and scientific lasers fall into this class.

1.2 The mechanism of laser damage is mainly the thermal effect of laser, light pressure and photochemical reaction. The injured parts are mainly the human eyes and skin. Damage to human eyes: It may cause damage to the cornea and retina. The location and range of the damage depend on the wavelength and level of the laser. The damage caused by laser to human eyes is relatively complex. Direct, reflected and diffusely reflected laser beams can all damage human eyes. Due to the focusing effect of the human eye, the infrared light (invisible) emitted by this laser is very harmful to the human eye. When this radiation enters the pupil, it will be focused on the retina and subsequently burn the retina, causing vision loss or even blindness. Damage to skin: Strong infrared lasers cause burns; ultraviolet lasers may cause burns, skin cancer, and enhance skin aging. Laser damage to the skin is manifested by causing varying degrees of rashes, blisters, pigmentation, and ulcers, until the subcutaneous tissue is completely destroyed.

1.3 Protective glasses
The light emitted by the laser is invisible radiation. Due to the high power, even the scattered beam may still cause irreversible damage to the glasses. This laser does not come with laser eye protection equipment, but such eye protection equipment must be worn at all times during laser operation. Laser safety glasses are all effective at specific wavelengths. When choosing suitable laser safety glasses, you need to know the following information: 1. Laser wavelength 2. Laser operation mode (continuous light or pulsed light) 3. Maximum exposure time (considering the worst case scenario) 4. Maximum irradiation power density (W/cm2) or maximum irradiation energy density (J/cm2) 5. Maximum allowable exposure (MPE) 6. Optical density (OD).

1.4 Electrical damage
The power supply voltage of laser equipment is three-phase alternating current 380V AC. The installation and use of laser equipment need to be properly grounded. During use, you need to pay attention to electrical safety to prevent electric shock injuries. When disassembling the laser, the power switch must be turned off. If electrical injury occurs, correct treatment measures should be taken to prevent secondary injuries. Correct treatment procedures: turn off the power, safely release personnel, call for help, and accompany the injured.

1.5 Mechanical damage
When maintaining and repairing the laser, some parts are heavy and have sharp edges, which may easily cause damage or cuts. You need to wear protective gloves, anti-smash safety shoes and other protective equipment.​

1.6 Gas and dust damage
When laser processing is performed, harmful dust and toxic gases will be produced. The workplace must be properly equipped with ventilation and dust collection devices, or wear masks for protection.

1.7 Safety recommendations
1. The following measures can be taken to improve the safety of laser equipment:
2. Limit access to laser facilities. Clarify access rights to the laser processing area. Restrictions can be implemented by locking the door and installing warning lights and warning signs on the outside of the door.
3. Before entering the laboratory for light operation, hang a light warning sign, turn on the light warning light, and notify surrounding personnel.
4. Before powering on the laser, confirm that the equipment’s intended safety devices are used correctly. Includes: light baffles, fire-resistant surfaces, goggles, masks, door interlocks, ventilation equipment, and fire-extinguishing equipment.
5. After using the laser, turn off the laser and power supply before leaving.​
6. Develop safe operating procedures, maintain and revise them regularly, and strengthen management. Conduct safety training for employees to improve their awareness of hazard prevention.