What are the hazards of hand welding, oxygen welding and argon arc welding to human body?

1. Possible occupational disease: welder's pneumoconiosis.

2, industry examples:

(1) Sporting goods manufacturing: copper tube punching

(2) Machinery industry: manual arc welding, gas shielded welding, argon arc welding, carbon arc gouging and gas welding.

(3) Transportation equipment manufacturing: locomotive parts assembly, platform assembly, ship pipeline installation, ship electrical installation, ship anchor chain, welding hazards and influencing factors.

There are many hazards of electric welding to health, which can be generally divided into physical factors and chemical factors. The former includes ultraviolet and infrared rays generated by high temperature arc light. The latter is various components of welding aerosol, including solid metals such as iron, manganese, aluminum, chromium, lead, nickel and radioactive elements, and gaseous gases such as manganese oxide, hydrogen fluoride and nitrogen oxides [1]. High temperature, vibration and noise are not obvious.

Welding aerosol has high dispersibility and its biological activity is obviously higher than other dusts. The composition of welding aerosol varies greatly with different covered electrode and welding methods, and its biological activity is also different [2]; Biological activity is also related to the solubility and freshness of welding fume.

2. Damage of welding operation to workers' health

2. 1 Effect of welder's pneumoconiosis on lung function

During arc welding, the core, coating and base metal in covered electrode are melted, evaporated, oxidized and agglomerated at high arc temperature, which produces a lot of dust of metal oxides and other substances, which can cause welder's pneumoconiosis if inhaled for a long time. Welder's pneumoconiosis generally occurs in a closed and poorly ventilated working environment, and the average length of service is about 18 years [3]. The measurement of lung ventilation function shows that exposure to welding dust can damage the lung ventilation function of welders to a certain extent, and the indexes of lung ventilation function such as FVC, FEV 1.0, FEV 1.0%, MMF, V50, V25 and PEFR are obviously reduced [4]. Smoking and dust exposure may have a synergistic effect on the pulmonary ventilation function of welders. The damage of lung ventilation function of welders tends to be aggravated with the extension of dust exposure time [5].

2.2 manganese poisoning

All kinds of weldments and covered electrode contain different amounts of manganese. Generally, the manganese content in the core is very low, only about 0.3~0.6%. In order to improve the mechanical strength, wear resistance, corrosion resistance and other properties, when covered electrode containing manganese is used, the manganese content can be as high as 23%. Welding in places with poor ventilation, such as cabins, boilers or closed containers, and long-term inhalation of manganese-containing smoke can cause manganese poisoning, which can detect manganese bleeding, increased urine manganese and changes in neurobehavioral functions [6]. The determination of hair manganese can also be used as an early screening index for manganese poisoning [7].

2.3 welding smoke heat

Welding fume heat, also known as welder heat, is a kind of metal fume heat. It is a systemic disease, which is mainly manifested by the sudden increase of body temperature and the increase of peripheral white blood cell count caused by inhalation of metal oxides. It usually begins at 6- 12 hours after exposure to metal oxide smoke [8], and dizziness, fatigue, chest tightness, shortness of breath, muscle joint pain, followed by fever, leukocytosis and even chills occur.

2.4 Effects on nervous system

A large number of studies show that there is nervous system damage related to occupational exposure in welding operation, which mainly involves information processing functions such as memory, analysis and location, showing abnormal neurophysiology, neuropsychology and neurobehavior [9], which is closely related to manganese, aluminum and lead in welding dust. Use who. NCTB test showed that the total score of behavioral function was negatively correlated with urinary manganese [10], suggesting that the change of neurobehavioral function can be used as one of the early indicators to prevent manganese poisoning [1 1]. Foreign studies have reported that the total score of behavioral function of electric welding workers is higher than that of the control group. The author analyzes that it may be caused by the health effect of workers and the training effect of job-related skills [12]. The influence of electric welding on the investigation function of workers' parasympathetic nerves has also been reported [13]. It has been reported abroad that the onset age of welder's Parkinson's syndrome is obviously earlier [14] (the average age is 46 years old, and the average age of control group is 63 years old), suggesting that welding work is one of the risk factors of Parkinson's syndrome.

2.5 Effects on eyes and skin

The harm of ultraviolet rays (UVR) and infrared rays (IFR) to eyes and skin is an important aspect of occupational injuries in electric welding. It is often reported that the eye symptoms of welders are obviously increased, such as electro-optic ophthalmia, chronic blepharitis, conjunctivitis and lens opacity, and the prevalence of chronic blepharitis and conjunctivitis tends to increase with the increase of working age [15]. The main damage caused by UVR overexposure is photosensitive keratitis, and the welder's cataract is related to infrared exposure. Recent studies abroad show that workers exposed to excessive UVR are at risk of non-melanoma skin cancer [16] and other chronic diseases such as malignant melanoma of the eye [17].

2.6 Effects on reproductive system

The outcome of reproductive toxicity is of great significance, so in recent 10 years, some studies on reproductive toxicity of electric welding have been carried out at home and abroad, mainly involving the semen quality of male workers, reproductive outcome of female workers and injury mechanism. The research shows that the menstrual flow, shortened cycle, prolonged menstrual period, increased leucorrhea, spontaneous abortion, premature delivery and dysmenorrhea of female welders are higher than those of the control group [18]. The semen appearance of male workers with manganese poisoning is even grayish white, and the PH value is normal. The average liquefaction time was longer than that of the control group. The results showed that the average ejaculation volume, total sperm count, sperm survival rate and activity rate of male workers with manganese poisoning were lower than those of the control group, and the sperm abnormality rate of male workers with manganese poisoning was significantly higher than that of the control group [19]. It is considered that manganese metal can affect the spermatogenic system of male workers, have a direct toxic effect on sperm development, and can kill sperm, thus causing changes in male semen quality. It has also been reported abroad that the sex hormone secretion of welders has changed and the sperm quality has decreased, but it has no effect on the sex ratio of offspring [20].

2.7 Effects on the levels of enzymes and antibodies in vivo

In recent years, there are many reports about the influence of electric welding on enzymes and antibodies in workers. The results showed that the total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) in welders' serum decreased significantly, and the level of malondialdehyde (MDA) increased significantly, but there was no dose-effect relationship [2 1, 22]. When welders are under oxidative stress, their antioxidant capacity is weakened, which indicates that the biofilm is destroyed [23].

In order to explore the influence of welding dust on human immunoglobulin content, the contents of IgG, IgA and IgM in serum of welders and healthy controls were determined by one-way immunoagar diffusion method. The results showed that the contents of IgG and IgA in welding group were significantly different from those in control group (P

Heat stress proteins (HSPs) are a group of highly conserved proteins in evolution, which are induced by various stress states. Under physiological conditions, they are necessary for the survival of cells. Under the stress condition, the increase of its level can improve the endurance and stress ability of sprinters to injury, thus protecting tissues and cells from the damage of harmful families and playing an important role in maintaining the stability of the body itself. The level of HSP65 antibody in plasma of welders was detected by enzyme-linked immunosorbent assay. The results showed that the plasma antibody level of welders was higher than that of the control group (P < 0.05). Among them, the abnormal detection rate is 26.65438 0%, and it is considered that welding mixed dust can induce the synthesis of HSP65 antibody in vivo [25]. Therefore, it is considered that the antibody level of HSDP65 in welder plasma can reflect the harm degree of welding mixed dust to workers.

2.8 Influence on internal organs

To explore the influence of electric welding on the liver and spleen of workers through B-ultrasound examination. Results The length and thickness of the left liver, the thickness of the right oblique liver and the thickness of the spleen in the welding group were higher than those in the control group, and the difference was significant. Electric welding has certain damage to the liver and spleen of workers, and it tends to increase with the increase of working age [26]. It has been reported abroad that the risk of pancreatic endocrine tumors in welders is also significantly higher than that in normal people [27].

2.9 Effects on Trace Elements in the Body

It is reported that five trace elements of manganese, copper, zinc, iron and lead in the serum of manganese welding workers were detected by plasma emission spectrometer. Results The contents of serum manganese and iron in the exposed group were significantly higher than those in the control group (P < 0.0 1), and the content of copper was slightly higher than that in the control group, but the difference was not statistically significant (P > 0.05). The contents of zinc and lead in serum were significantly lower than those in control group (P < 0.0 1). The length of service and age of the exposed group showed that there was no statistical significance in the comparison of serum trace elements among the groups. Conclusion: Excessive inhalation of manganese can affect the changes of manganese, copper, zinc, iron and lead in the body, thus causing the imbalance of trace elements in the body and promoting the occurrence of manganese poisoning [28]. It is also reported that the content of manganese in red blood cells of electric welders is higher than that of men, and the changes of copper and zinc content in red blood cells are positively correlated with manganese [29].

Argon arc welding is more harmful than covered electrode arc welding, but it is not daunting. The infrared radiation is about 1 ~ 1.5 times that of ordinary covered electrode arc welding, and the ultraviolet radiation generated by argon arc welding is about 5 ~ 30 times that of covered electrode arc welding. When welding in a limited space, the concentration of ozone can increase to a dangerous level, and carbon dioxide and carbon monoxide will also be produced during welding. Therefore, it is necessary to do a good job in welding process, choose electrode materials and try to choose thorium, tungsten, cerium and tungsten with low radioactivity. Wear masks and gloves when polishing electrodes and wash your hands after work; If welding is carried out for a long time, we should have regular physical examination, so that we can have a good job, just like we bask in the sun, which is bad for our health for a long time.

Electric ophthalmia

Some people are blinded by electric welding during the day, and suddenly they can't open their eyes at night, causing severe pain and tears in their eyes. This is often electro-optic ophthalmia.

Arc light of electric welding and gas welding, ultraviolet lamp, and sunlight reflection from seashore, plateau and snow-capped mountains under the scorching sun can produce a lot of ultraviolet rays, causing electro-optic ophthalmia, especially for welders. The main manifestations of electro-optic inflammation limitation are: 2 ~ 12 hours after eyes are irradiated by ultraviolet rays, patients feel eye pain, fear of light, and it is difficult to open their eyes. Eye pain is like a lot of sand entering his eyes, and his vision is blurred. Ophthalmic examination showed eyelid skin congestion, envy, conjunctival congestion and edema, corneal epithelial shedding. Electro-optic service inflammation, although dangerous, has a good prognosis. Topical anesthetic (such as 0.5% dicaine solution) 1 ~ 2 times can immediately eliminate the symptoms of eye pain, and anti-inflammatory eye water can be dripped to prevent infection. With the rapid repair of conjunctiva and corneal epithelium, it can be cured in 2 ~ 5 days.

In order to prevent electro-optic ophthalmia, welders must wear protective masks or glasses when operating. In addition, ultraviolet rays reflected by sunlight in plateau, snow or desert can also cause electro-optic ophthalmia, so it is necessary to wear protective glasses.

Compared with covered electrode arc welding, argon arc welding is more harmful to people's health. As long as you pay attention to protection during work, it is not harmful to people's health. We all know that argon arc welding has high current density and strong light ratio. The ultraviolet radiation produced by the arc is about 5 ~ 30 times that of ordinary covered electrode arc welding, and the infrared radiation is about 1 ~ 1.5 times that of covered electrode arc welding. The ozone content produced in the welding process is very high. Therefore, try to choose a ventilated place for welding, and the protective measures for argon arc welding are basically the same as those for manual arc welding. Work should be a combination of work and rest, pay attention to physical exercise at ordinary times, and take part in more sports activities, because welders are special operators, and the degree of harm in their work is relatively higher than other types of work!

I wish you the best of health! safety first