Basic information about nitrogen and argon
Nitrogen is a colorless and odorless gas.
Ferrous metallurgy enterprises use 95-97% pure nitrogen; pure nitrogen with an impurity content of less than 0.01% and liquid nitrogen with a purity of more than 99%. When liquid nitrogen containing a small amount of oxygen evaporates, the nitrogen evaporates first, as a result of which the oxygen concentration in the liquid increases and can reach values at which there is a danger of fire and explosion of a number of substances and materials in it.
Argon is a colorless and odorless gas. When cooled to the temperatures of liquid nitrogen and liquid argon, many materials become brittle.
Argon is heavier than air and can accumulate in pits, wells, and dead ends, displacing air. The oxygen content may drop below the limit values. Equalization of concentration due to diffusion occurs slowly and depends on volumes, geometric shapes, the flow of argon into the atmosphere, and its temperature. The temperature of the nitrogen or argon is of great importance. So, despite the fact that nitrogen is lighter than air, it, like argon, can accumulate in pits and wells if the temperature of the incoming nitrogen is lower than the air temperature.
Are aluminum cookware poisonous?
From a chemical point of view, pure metal in air very quickly becomes covered with a protective film of oxide. You can check this by rubbing an aluminum pan with sandpaper. Very soon the shiny surface will become matte again. Previously, it was believed that if an oxide film quickly covers metallic aluminum, then the metal of which the cookware is made is safe. But about 30 years ago, experiments were carried out that showed that aluminum is far from safe, it changes the energy metabolism of cellular structures, and promotes the development of malignant tumors. And dishes are one of the most open gates for the penetration of this element inside.
Aluminum utensils in a public canteen - such places still use aluminum utensils to cook food in.
Aluminum cookware is very popular because this metal is an excellent conductor of heat, even thick-walled products heat up very quickly. What harm does a cast aluminum frying pan cause? It is known that thick-bottomed cauldrons, cauldrons and various pots are still produced from this metal. There are also small kitchen utensils: forks, spoons, colanders, sieves and other items. It is purchased in large quantities by the poor, since both its cost and retail price are much lower than the price of enamel cookware. But now many countries have moved away from using metal in dishes.
In our country there are more than a dozen industrial enterprises that produce these products. Such factories exist in Belgorod, Kamensk-Uralsky, and other cities. How does aluminum enter the body?
After thoroughly washing the dishes, they are damaged by various metal sponges and aluminum shavings appear. It is not visible, but it penetrates into food in microdoses. The oxide film does not always help, since quite often the dishes are washed and cleaned immediately before cooking. The result is a diffusion of atoms into food products.
Washing aluminum dishes
Experts in hygienic testing of utensils recommend only boiling water in such cheap utensils.
If you boil acidic foods in an aluminum pan, for example, cranberry juice or rhubarb decoction, then the concentration of metal in such solutions increases many times over.
There is a decree of the Chief State Doctor of the Russian Federation, which prohibits the use of aluminum cookware in children's catering establishments.
The widespread use of food foil made from this element, as well as Tetra Pak-type packaging, significantly increases the risk of chronic intoxication with aluminum. In such packaging there is an inner layer of foil that is in direct contact with the food product, for example, berry juices for baby food.
Composition of Tetra Pak packaging - layers
Therefore, the harm from cookware made of cast aluminum is not as great, since it is still used quite rarely, as the harm from all kinds of packages with juices, which are purchased in large quantities, and which often contain acidic contents. An ideal option for long-term storage of food products, including baby food, is glass containers.
Many scientists believe that bulk products, such as salt, cereals and sugar, cannot even be stored in aluminum containers. Aluminum is a soft metal, and transfers to the surface of bulk products, and then ends up in food. If foods react actively, metal may leach from cans or foil into the food. This often results in the production of tomato sauce and coffee in boilers made of this metal.
Therefore, if you want to preserve your health and the health of your children, then refuse to use cast aluminum cookware: there is no benefit from it, but only one harm. Buy juices in supermarkets only in glass containers. This advice is very difficult to follow, since such juices are not always sold and are quite expensive.
Video: How Tetra Pak packaging is made
In addition to the above facts, you need to take into account that there is food coloring E 173, which, although prohibited for use in a number of countries, is used in Russia. This additive is used to decorate confectionery products, various cakes and dragees. The use of this additive gives the surface of confectionery products a shiny and silvery tint.
Cake with E173 additive
There is also a food stabilizer E 520 - aluminum sulfate. The largest consumer of sulfate is canning factories. Some types of fish are treated with this compound; it prevents the breakdown of muscle fibers and preserves its presentation. This stabilizer is also used to thicken egg whites, as well as for the production of candied fruits. In some cases, aluminum sulfate is used as a leavening agent.
Application of nitrogen and argon
Nitrogen gas is used in fire extinguishing installations, for cooling the gearbox of the bellless loading device of blast furnaces, for sealing gas exhaust tractors of converters, for the production of protective atmospheres, etc.
Liquid nitrogen - for processing parts in the chief mechanic's shops, laboratories, etc., and after gasification - for various technological needs at enterprises that do not have their own oxygen stations.
Argon is used in significant quantities in steel shops to improve the quality of steel, as well as in welding and cutting.
Nitrogen and argon are delivered to consumers in three ways. Through pipelines, mainly at the enterprises that produce them. At these enterprises, as a rule, there are networks of main argon and nitrogen pipelines. In cylinders or recipients under a pressure of 150-165 kgf/cm2, nitrogen and argon are used in places with small volumes of consumption or when there is a periodic need for these gases. When there is a large demand for these gases and a significant distance from the production site, nitrogen and argon are delivered in liquid form, followed by gasification in special installations. Liquid nitrogen is also used as a coolant for occasional work. For example, for freezing soil during foundation construction, destruction of old foundations, extinguishing fires in mines, etc.
The rapid increase in the use of nitrogen and argon in various processes and the lack of necessary and accessible information about the properties of these gases and their effect on the human body are the main causes of accidents.
The information below on the effect of an atmosphere with a low oxygen content on the human body and first aid measures uses data from the Institute of Medical and Biological Problems and the Institute of Biophysics.
Treatment
A specific antidote that improves the patient's health with aluminum poisoning is deferoxamine. This drug is used to treat what is called dialysis encephalopathy and osteomalacia, or softening of the bone. In patients with aluminum intoxication, it is recommended to use deferoxamine only in cases where the concentration of aluminum in the blood plasma exceeds 200 mcg per milliliter. This drug is not sold in pharmacies and cannot be purchased; it is found in hemodialysis centers where artificial kidney machines are installed.
Deferoxamine
Treatment of aluminum poisoning also involves symptomatic therapy: combating bronchospasm, breathing oxygen, relieving convulsions, using B vitamins to treat encephalopathy, and using special drugs to relieve extrapyramidal disorders.
In conclusion, we can say that the benefits and harms of aluminum for humans are obvious. Therefore, it is necessary to remember that aluminum intoxication is much easier to prevent than to treat it. This metal is found very widely both in industry and in everyday life, and each person can take appropriate measures to reduce their contact with this necessary and such insidious metal.
Below we suggest watching some interesting videos about the dangers of aluminum:
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Harm from welding and occupational diseases of welders
Electric welding is, of course, a harmful process that is associated not only with the release of chemicals, but also with high temperatures, as well as bright ultraviolet radiation. It’s not for nothing that welders are given milk because it’s harmful. So, without proper protection, welding causes irreparable harm to human health.
But even under the reliable protection of a welding mask and overalls, there is such a thing as an occupational disease. Welders who have worked for 20-30 years develop their own illnesses, which are characterized by a combination of occupational diseases.
How harmful is welding? What occupational diseases do welders suffer from, and what can be done to avoid illnesses?
Physiological effects of nitrogen and argon on humans
Argon and nitrogen are physiologically inert, non-toxic gases. By replacing oxygen in the air and displacing oxygen from the body, they act on humans as suffocating agents (asphyxants) due to a decrease in the partial pressure of oxygen.
With a slow decrease in oxygen content in the atmosphere to a level that is briefly tolerated by the body (5-7%), symptoms are detected:
• increased breathing and heart rate, the breathing rhythm can be wave-like (periods of increased breathing are followed by periods of slowing); • loss of balance, dizziness, possible euphoria; • a feeling of heaviness or squeezing in the frontal part of the head; • knocking in the temples; • feeling of heat throughout the body; • tingling sensation in the tongue, tips of the fingers and toes; • difficulty speaking; • progressively (possibly quickly) decreasing physical performance, loss of coordination; • changes in the perception of the environment and inhibition of the function of the senses, especially touch; • memory lapses and loss of consciousness are possible.
Symptoms may appear depending on a person’s individual predisposition to the effects of hypoxia.
With a sharp decrease in oxygen content in the atmosphere and, especially if a person accidentally enters the environment of nitrogen or argon, a few breaths are enough to reduce the partial pressure of oxygen in the blood to a critical level - loss of consciousness occurs, almost always suddenly.
There is no difference in the impact of argon or nitrogen on a person when they completely displace oxygen from the atmosphere.
When inhaling a hypoxic, but tolerated by the body, mixture of air with argon, unlike nitrogen, a weak narcotic effect of argon may individually manifest itself, expressed by slight euphoria. But this is not of fundamental importance regarding the threatening danger.
Harm from welding with an inverter and occupational diseases of welders
When welding metals, the welder is affected by three main factors that are considered negative. First of all, this is:
- Chemical factor - the welding process proceeds with the release of harmful chemicals. Melting of metal is characterized by the release of gases and vapors that cannot be inhaled.
- Ultraviolet radiation is the main enemy of a welder’s health; it is the ultraviolet radiation that occurs as a result of electric welding. Over time, if the eyes are constantly exposed to harmful ultraviolet radiation, vision decreases, and this is also an occupational disease for all welders.
- Physical factor - metal welding is associated with various physical activities, among which monotonous work also occurs. First of all, these are constantly repeated movements and postures in which the welder must be continuously in order to perform his job efficiently.
You can avoid many diseases from welding if you strictly follow the rules and safety precautions when performing electric welding work.
Rules for working with electric welding
The welding process is the most powerful in producing infrared radiation. You don’t even have to go to the solarium, just put the mask and overalls aside and cook without them. Moreover, novice welders pay little attention to this, and think that if they have protected their eyes, then they don’t even need to cover the rest, open parts of the body.
Therefore, the first and main rule when working with electric welding is to reliably protect the eyes and open parts of the body from the harmful effects of ultraviolet radiation. Fortunately, today you can buy very high-quality workwear and automatic masks for welding, which will help protect your eyes from electroophthalmia and visual impairment from welding.
The chemical factor, which was already mentioned above in this article on the site about manual arc welding mmasvarka.ru, also causes no less harm to the welder. Welding in a closed room, and even without good ventilation, can lead to poisoning by combustion products of metals and electrode coating.
That is why welding work should be carried out outdoors or in rooms with good ventilation. At the same time, it is important not to forget about fire safety rules when welding, which in no case should be neglected.
