Lesson "infrared, ultraviolet, x-ray radiation" for the specialty "welder". How are infrared rays different from ultraviolet rays?

I remember disinfection with UV lamps from childhood - in the kindergarten, sanatorium and even in the summer camp there were somewhat frightening structures that glowed with a beautiful purple light in the dark and from which the educators drove us away. So what is it really ultraviolet radiation And why does a person need it?

Perhaps the first question to be answered is what ultraviolet rays are and how they work. It's usually called electromagnetic radiation, which is in the range between visible and X-ray radiation. Ultraviolet is characterized by a wavelength from 10 to 400 nanometers.
It was discovered back in the 19th century, and this happened thanks to the discovery of infrared radiation. Having discovered the IR spectrum, in 1801 I.V. Ritter drew attention to the opposite end of the light spectrum during experiments with silver chloride. And then several scientists at once came to the conclusion about the heterogeneity of the ultraviolet.

Today it is divided into three groups:

• UV-A radiation - near ultraviolet;
• UV-B - medium;
• UV-C - far.

This division is largely due to the impact of rays on a person. The natural and main source of ultraviolet radiation on Earth is the Sun. In fact, it is from this radiation that we are saved by sunscreens. At the same time, far ultraviolet is completely absorbed by the Earth's atmosphere, and UV-A just reaches the surface, causing a pleasant tan. And on average, 10% of UV-B provokes the same sunburn, and can also lead to the formation of mutations and skin diseases.

Artificial sources of ultraviolet radiation are created and used in medicine, agriculture, cosmetology and various sanitary institutions. Generation of ultraviolet radiation is possible in several ways: by temperature (incandescent lamps), by the movement of gases (gas lamps) or metal vapors (mercury lamps). At the same time, the power of such sources varies from a few watts, usually small mobile radiators, to a kilowatt. The latter are mounted in volumetric stationary installations. The areas of application of UV rays are due to their properties: the ability to accelerate chemical and biological processes, the bactericidal effect and the luminescence of certain substances.

Ultraviolet is widely used to solve a variety of problems. In cosmetology, the use of artificial UV radiation is used primarily for tanning. Solariums produce rather mild UV-A according to the introduced standards, and the share of UV-B in tanning lamps is no more than 5%. Modern psychologists recommend solariums for the treatment of "winter depression", which is mainly caused by vitamin D deficiency, as it is formed under the influence of UV rays. Also, UV lamps are used in manicure, since it is in this spectrum that especially resistant gel polishes, shellac and the like dry out.

Ultraviolet lamps are used to create photographs in non-standard situations, for example, to capture space objects that are invisible with a conventional telescope.

Ultraviolet is widely used in expert activities. With its help, the authenticity of the paintings is checked, since fresher paints and varnishes in such rays look darker, which means that the real age of the work can be established. Forensics also use UV rays to detect traces of blood on objects. In addition, ultraviolet light is widely used to develop hidden seals, security features and document authentication threads, as well as in the lighting design of shows, restaurant signs or decorations.

In medical institutions ultraviolet lamps used to sterilize surgical instruments. In addition, air disinfection using UV rays is still widespread. There are several types of such equipment.

This is the name of mercury lamps of high and low pressure and xenon flash lamps. The bulb of such a lamp is made of quartz glass. The main advantage of germicidal lamps - long term services and instant ability to work. Approximately 60% of their rays are in the bactericidal spectrum. Mercury lamps are quite dangerous in operation; in case of accidental damage to the housing, thorough cleaning and demercurization of the room is necessary. Xenon lamps are less dangerous if damaged and have a higher bactericidal activity. Also germicidal lamps divided into ozone and non-ozone. The former are characterized by the presence in their spectrum of a wave with a length of 185 nanometers, which interacts with oxygen in the air and turns it into ozone. High concentrations of ozone are dangerous for humans, and the use of such lamps is strictly limited in time and is recommended only in a ventilated area. All this led to the creation of ozone-free lamps, on the flask of which special coating, which does not transmit a wave of 185 nm outward.

Regardless of the type, bactericidal lamps have common drawbacks: they work in complex and expensive equipment, the average life of the emitter is 1.5 years, and the lamps themselves, after burnout, must be stored packed in a separate room and disposed of in a special way in accordance with current regulations.

Consist of a lamp, reflectors and other auxiliary elements. Such devices are of two types - open and closed, depending on whether UV rays pass out or not. Open emit ultraviolet, enhanced by reflectors, into the space around, capturing almost the entire room at once, if installed on the ceiling or wall. It is strictly forbidden to treat the premises with such an irradiator in the presence of people.
Closed irradiators work on the principle of a recirculator, inside which a lamp is installed, and the fan draws air into the device and releases the already irradiated air to the outside. They are placed on the walls at a height of at least 2 m from the floor. They can be used in the presence of people, but long-term exposure is not recommended by the manufacturer, as part of the UV rays can pass out.
Among the shortcomings of such devices, one can note immunity to mold spores, as well as all the difficulties of recycling lamps and strict regulations for use, depending on the type of emitter.

Germicidal installations

A group of irradiators combined into one device used in one room is called a bactericidal installation. Usually they are quite large and are characterized by high power consumption. Air treatment with bactericidal installations is carried out strictly in the absence of people in the room and is monitored according to the Commissioning Certificate and the Registration and Control Log. It is used only in medical and hygienic institutions for disinfection of both air and water.

Disadvantages of ultraviolet air disinfection

In addition to those already listed, the use of UV emitters has other disadvantages. First of all, ultraviolet itself is dangerous for the human body, it can not only cause skin burns, but also affect work of cardio-vascular system dangerous for the retina. In addition, it can cause the appearance of ozone, and with it the unpleasant symptoms inherent in this gas: irritation of the respiratory tract, stimulation of atherosclerosis, exacerbation of allergies.

The effectiveness of UV lamps is quite controversial: the inactivation of pathogens in the air by permitted doses of ultraviolet radiation occurs only when these pests are static. If microorganisms move, interact with dust and air, then the required radiation dose increases by 4 times, which a conventional UV lamp cannot create. Therefore, the efficiency of the irradiator is calculated separately, taking into account all the parameters, and it is extremely difficult to choose the right ones for influencing all types of microorganisms at once.

Penetration of UV rays is relatively shallow, and even if the immobile viruses are under a layer of dust, the upper layers protect the lower ones by reflecting ultraviolet from themselves. So, after cleaning, disinfection must be carried out again.
UV irradiators cannot filter the air, they only fight microorganisms, keeping all mechanical pollutants and allergens in their original form.

Oxygen, sunlight and water contained in the Earth's atmosphere are the main conditions conducive to the continuation of life on the planet. Researchers have long proven that the intensity and spectrum of solar radiation in the vacuum that exists in space remains unchanged.

On Earth, the intensity of its impact, which we call ultraviolet radiation, depends on many factors. Among them: the season, the geographical location of the area above sea level, the thickness of the ozone layer, cloudiness, as well as the level of concentration of industrial and natural impurities in the air masses.

Ultra-violet rays

Sunlight reaches us in two ranges. The human eye can only distinguish one of them. Ultraviolet rays are in the spectrum invisible to humans. What are they? It is nothing but electromagnetic waves. The length of ultraviolet radiation is in the range from 7 to 14 nm. Such waves carry huge flows of thermal energy to our planet, which is why they are often called thermal waves.

By ultraviolet radiation it is customary to understand an extensive spectrum consisting of electromagnetic waves with a range conditionally divided into far and near rays. The first of them are considered vacuum. They are completely absorbed by the upper atmosphere. Under the conditions of the Earth, their generation is possible only in the conditions of vacuum chambers.

As for near ultraviolet rays, they are divided into three subgroups, classified by range into:

Long, ranging from 400 to 315 nanometers;

Medium - from 315 to 280 nanometers;

Short - from 280 to 100 nanometers.

Measuring instruments

How does a person determine ultraviolet radiation? To date, there are many special devices designed not only for professional, but also for domestic use. They measure the intensity and frequency, as well as the magnitude of the received dose of UV rays. The results allow us to evaluate them possible harm for the body.

UV Sources

The main "supplier" of UV rays on our planet is, of course, the Sun. However, to date, artificial sources of ultraviolet radiation have been invented by man, which are special lamp devices. Among them:

Mercury-quartz lamp high pressure, capable of operating in the general range from 100 to 400 nm;

Fluorescent vital lamp generating wavelengths from 280 to 380 nm, the maximum peak of its radiation is between 310 and 320 nm;

Ozone-free and ozone germicidal lamps that produce ultraviolet rays, 80% of which are 185 nm long.

The benefits of UV rays

Similar to the natural ultraviolet radiation coming from the Sun, the light produced by special devices affects the cells of plants and living organisms, changing their chemical structure. Today, researchers know only a few varieties of bacteria that can exist without these rays. The rest of the organisms, once in conditions where there is no ultraviolet radiation, will certainly die.

UV rays can have a significant impact on ongoing metabolic processes. They increase the synthesis of serotonin and melatonin, which positive influence on the work of the central nervous, as well as endocrine system. Under the influence of ultraviolet light, the production of vitamin D is activated. And this is the main component that promotes the absorption of calcium and prevents the development of osteoporosis and rickets.

Harm of UV rays

Harsh ultraviolet radiation, detrimental to living organisms, does not let the ozone layers in the stratosphere reach the Earth. However, rays in the middle range, reaching the surface of our planet, can cause:

Ultraviolet erythema - a severe burn of the skin;

Cataract - clouding of the lens of the eye, which leads to blindness;

Melanoma is skin cancer.

In addition, ultraviolet rays can have a mutagenic effect, cause malfunctions in the immune forces, which causes oncological pathologies.

Skin lesion

Ultraviolet rays sometimes cause:

1. Acute skin lesions. Their occurrence is facilitated by high doses of solar radiation containing mid-range rays. They act on the skin for a short time, causing erythema and acute photodermatosis.
2. Delayed skin injury. It occurs after prolonged exposure to long-wave UV rays. These are chronic photodermatitis, solar geroderma, photoaging of the skin, the occurrence of neoplasms, ultraviolet mutagenesis, basal cell and squamous cell skin cancer. This list also includes herpes.

Both acute and delayed damage is sometimes caused by excessive exposure to artificial sunbathing, as well as visits to those tanning salons that use non-certified equipment or where UV lamps are not calibrated.

Skin protection

The human body, with a limited amount of any sunbathing, is able to cope with ultraviolet radiation on its own. The fact is that over 20% of such rays can delay a healthy epidermis. To date, UV protection to avoid the occurrence of malignant formations, will require:

Limiting the time spent in the sun, which is especially important during the summer midday hours;

Wearing light, but at the same time closed clothing;

Selection of effective sunscreens.

Using the bactericidal properties of ultraviolet light

UV rays can kill fungus, as well as other microbes that are on objects, wall surfaces, floors, ceilings and in the air. In medicine, these bactericidal properties of ultraviolet radiation are widely used, and their use is appropriate. Special lamps that produce UV rays ensure the sterility of surgical and manipulation rooms. However, ultraviolet bactericidal radiation is used by doctors not only to combat various nosocomial infections, but also as one of the methods for eliminating many diseases.

Phototherapy

The use of ultraviolet radiation in medicine is one of the methods of getting rid of various diseases. In the process of such treatment, a dosed effect of UV rays on the patient's body is produced. At the same time, the use of ultraviolet radiation in medicine for these purposes becomes possible due to the use of special phototherapy lamps.

A similar procedure is carried out to eliminate diseases of the skin, joints, respiratory organs, peripheral nervous system, and female genital organs. Ultraviolet light is prescribed to accelerate the healing process of wounds and to prevent rickets.

Especially effective is the use of ultraviolet radiation in the treatment of psoriasis, eczema, vitiligo, some types of dermatitis, prurigo, porphyria, pruritis. It is worth noting that this procedure does not require anesthesia and does not cause discomfort to the patient.

The use of a lamp that produces ultraviolet allows you to get a good result in the treatment of patients who have undergone severe purulent operations. In this case, the bactericidal property of these waves also helps patients.

The use of UV rays in cosmetology

Infrared waves are actively used in the field of maintaining human beauty and health. Thus, the use of ultraviolet germicidal radiation is necessary to ensure sterility. various premises and appliances. For example, it can be the prevention of infection of manicure tools.

The use of ultraviolet radiation in cosmetology is, of course, a solarium. In it, with the help of special lamps, customers can get a tan. It perfectly protects the skin from possible subsequent sunburns. That is why cosmetologists recommend having several sessions in the solarium before traveling to hot countries or to the sea.

Necessary in cosmetology and special UV lamps. Thanks to them, there is a rapid polymerization of a special gel used for manicure.

Determination of electronic structures of objects

Finds its use in ultraviolet radiation and in physical research. With its help, the spectra of reflection, absorption and emission in the UV region are determined. This allows you to clarify electronic structure ions, atoms, molecules and solids.

The UV spectra of stars, the Sun and other planets carry information about those physical processes that occur in hot regions of space objects under study.

Water purification

Where else are UV rays used? Ultraviolet germicidal radiation finds its application for disinfection drinking water. And if earlier chlorine was used for this purpose, today it has already been studied quite well. Negative influence on the body. So, vapors of this substance can cause poisoning. The ingestion of chlorine itself provokes the occurrence of oncological diseases. That is why ultraviolet lamps are increasingly being used to disinfect water in private homes.

UV rays are also used in swimming pools. Ultraviolet emitters to eliminate bacteria are used in the food, chemical and pharmaceutical industries. These areas also need clean water.

Air disinfection

Where else does a person use UV rays? The use of ultraviolet radiation for air disinfection is also becoming more common in recent years. Recirculators and emitters are installed in crowded places, such as supermarkets, airports and train stations. The use of UV radiation, which affects microorganisms, makes it possible to disinfect their habitat to the highest degree, up to 99.9%.

domestic use

Quartz lamps that produce UV rays have been disinfecting and purifying the air in clinics and hospitals for many years. However, in recent years, ultraviolet radiation has been increasingly used in everyday life. It is highly effective in eliminating organic contaminants such as fungus and mold, viruses, yeasts and bacteria. These micro-organisms spread particularly rapidly in rooms where people, for various reasons, tightly close windows and doors for a long time.

Usage bactericidal irradiator in living conditions becomes expedient with a small area of ​​\u200b\u200bhousing and big family with small children and pets. A UV lamp will allow rooms to be disinfected periodically, minimizing the risk of the onset and further transmission of diseases.

Similar devices are also used by tuberculosis patients. After all, such patients do not always receive treatment in a hospital. While at home, they need to disinfect their home, including using ultraviolet radiation.

Application in forensics

Scientists have developed a technology that allows detecting the minimum doses of explosives. For this, a device is used in which ultraviolet radiation is produced. Such a device is capable of detecting the presence of hazardous elements in the air and in water, on fabric, and also on the skin of a suspect in a crime.

Ultraviolet and infrared radiation also finds its application in macro photography of objects with invisible and hardly visible traces of a committed offense. This allows forensic scientists to study documents and traces of a shot, texts that have undergone changes as a result of their flooding with blood, ink, etc.

Other uses of UV rays

Ultraviolet radiation is used:

In show business to create lighting effects and lighting;

In currency detectors;

In printing;

In animal husbandry and agriculture;

For catching insects;

In restoration;

For chromatographic analysis.

Infrared radiation - this is a kind of electromagnetic radiation, which occupies a range from 0.77 to 340 microns in the spectrum of electromagnetic waves. In this case, the range from 0.77 to 15 microns is considered short-wave, from 15 to 100 microns - medium-wave, and from 100 to 340 - long-wave.

The short-wave part of the spectrum is adjacent to visible light, and the long-wave part merges with the region of ultrashort radio waves. So infrared radiation It has both the properties of visible light (it propagates in a straight line, reflects, refracts like visible light) and the properties of radio waves (it can pass through some materials that are opaque to visible radiation).

Infrared emitters with a surface temperature of 700 C to 2500 C have a wavelength of 1.55-2.55 microns and are called "light" - they are closer in wavelength to visible light, emitters with a lower surface temperature have a longer wavelength and are called "dark".

What is the source of infrared radiation?

Generally speaking, any body heated to a certain temperature radiates thermal energy in the infrared range of the spectrum of electromagnetic waves and can transfer this energy through radiant heat transfer to other bodies. Energy transfer occurs from a body with a higher temperature to a body with a lower temperature, while different bodies have different radiating and absorbing capacities, which depend on the nature of the two bodies, on the state of their surface, etc.

Application



Infrared rays are used for medical purposes if the radiation is not too strong. They have a positive effect on the human body. Infrared rays have the ability to increase local blood flow in the body, increase metabolism, and expand blood vessels.

• Remote control

Infrared diodes and photodiodes are widely used in remote controls, automation systems, security systems, etc. They do not distract a person's attention due to their invisibility.

• When painting

Infrared emitters are used in industry for drying paint surfaces. The infrared drying method has significant advantages over the traditional, convection method. First of all, this is, of course, an economic effect. The speed and energy expended with infrared drying is less than those with traditional methods.

• Food sterilization

With the help of infrared radiation, food products are sterilized for the purpose of disinfection.

• Anti-corrosion agent

Infra-red beams are applied, for the purpose of prevention of corrosion of the surfaces covered with a varnish.

• food industry

A feature of the use of IR radiation in Food Industry is the possibility of penetration of an electromagnetic wave into such capillary-porous products as grain, cereals, flour, etc. to a depth of up to 7 mm. This value depends on the nature of the surface, structure, properties of the material and the frequency response of the radiation. An electromagnetic wave of a certain frequency range has not only a thermal, but also a biological effect on the product, it helps to accelerate biochemical transformations in biological polymers (starch, protein, lipids). Conveyor drying conveyors can be successfully used when laying grain in granaries and in the flour-grinding industry.


Ultraviolet radiation (from ultra... and violet), ultraviolet rays, UV radiation, electromagnetic radiation invisible to the eye, occupying the spectral region between visible and X-ray radiation within wavelengths l 400-10 nm. Whole area Ultraviolet radiation conditionally divided into near (400-200 nm) and distant, or vacuum (200-10 nm); The last name comes from the fact that Ultraviolet radiation this area is strongly absorbed by air and its study is carried out using vacuum spectral instruments.

Positive Effects

In the twentieth century, it was first shown how UV radiation has a beneficial effect on humans. The physiological effect of UV rays was studied by domestic and foreign researchers in the middle of the last century (G. Varshaver. G. Frank. N. Danzig, N. Galanin. N. Kaplun, A. Parfenov, E. Belikova. V. Dugger. J. Hassesser, H. Ronge, E. Biekford, and others) |1-3|. It has been convincingly proven in hundreds of experiments that radiation in the UV region of the spectrum (290-400 nm) increases the tone of the sympathetic-adrenaline system, activates protective mechanisms, increases the level of nonspecific immunity, and also increases the secretion of a number of hormones. Under the influence of UV radiation (UVR), histamine and similar substances are formed, which have a vasodilating effect, increase the permeability of skin vessels. Changes in carbohydrate and protein metabolism in the body. The action of optical radiation changes pulmonary ventilation - the frequency and rhythm of breathing; increases gas exchange, oxygen consumption, activates the activity of the endocrine system. Particularly significant is the role of UV radiation in the formation of vitamin D in the body, which strengthens the musculoskeletal system and has an anti-rachitis effect. Of particular note is that long-term UVR deficiency can have adverse effects on the human body, referred to as "light starvation". The most common manifestation of this disease is a violation of mineral metabolism, decreased immunity, fatigue, etc.

Action on the skin

The action of ultraviolet radiation on the skin that exceeds the natural protective ability of the skin (tanning) leads to burns.

Prolonged exposure to ultraviolet radiation contributes to the development of melanoma, various kinds skin cancer, accelerates aging and the appearance of wrinkles.

With controlled exposure of the skin to ultraviolet rays, one of the main positive factors is the formation of vitamin D on the skin, provided that the natural fatty film is preserved on it. Sebum oil on the surface of the skin is exposed to ultraviolet light and then reabsorbed into the skin. But if you wash off the sebum before going out into the sun, vitamin D cannot be formed. If you take a bath immediately after sun exposure and wash off the fat, then vitamin D may not have time to be absorbed into the skin.

Action on the retina

Ultraviolet radiation is imperceptible to the human eye, but with intense exposure it causes a typical radiation injury (retinal burn). So, on August 1, 2008, dozens of Russians damaged the retina during solar eclipse, despite numerous warnings about the dangers of seeing him without eye protection. They complained of a sharp decrease in vision and a spot before their eyes.

Nevertheless, ultraviolet is extremely necessary for the human eye, as most ophthalmologists attest. Sunlight has a relaxing effect on the muscles around the eyes, stimulates the iris and nerves of the eyes, and increases blood circulation. Regularly strengthening the nerves of the retina with sunbathing, you will get rid of the painful sensations in the eyes that occur during intense sunlight.


Sources:

With the discovery of infrared radiation, the well-known German physicist Johann Wilhelm Ritter had a desire to study the opposite side of this phenomenon.

After some time, he managed to find out that at the other end it has considerable chemical activity.

This spectrum became known as ultraviolet rays. What it is and what effect it has on living terrestrial organisms, let's try to figure it out further.

Both radiations are in any case electromagnetic waves. Both infrared and ultraviolet, they limit the spectrum of light perceived by the human eye on both sides.

The main difference between these two phenomena is the wavelength. Ultraviolet has a fairly wide wavelength range - from 10 to 380 microns and is located between visible light and X-rays.

Differences between infrared and ultraviolet

IR radiation has the main property - to radiate heat, while ultraviolet has a chemical activity, which has a tangible effect on human body.

How does ultraviolet radiation affect humans?

Due to the fact that UV is divided by the difference in wavelength, they biologically affect the human body in different ways, so scientists distinguish three sections of the ultraviolet range: UV-A, UV-B, UV-C: near, middle and far ultraviolet.

The atmosphere that envelops our planet acts as a protective shield that protects it from the Sun's ultraviolet flux. Far radiation is retained and absorbed almost completely by oxygen, water vapor, carbon dioxide. Thus, insignificant radiation enters the surface in the form of near and medium radiation.

The most dangerous is radiation with a short wavelength. If short-wave radiation falls on living tissues, it provokes an instant destructive effect. But due to the fact that our planet has an ozone shield, we are safe from the effects of such rays.

IMPORTANT! Despite natural protection, we use some inventions in everyday life that are sources of this particular range of rays. This is welders and ultraviolet lamps, which, unfortunately, cannot be abandoned.

Biologically, ultraviolet radiation affects human skin like a slight redness, sunburn, which is a fairly mild reaction. But it is worth considering individual feature skin that can react specifically to UV radiation.

Exposure to UV rays also adversely affects the eyes. Many are aware that ultraviolet affects the human body in one way or another, but not everyone knows the details, so we will try to understand this topic in more detail.

UV mutagenesis or how UV affects human skin

Completely avoid exposure to sunlight skin covering you can't, it's going to lead to very unpleasant consequences.

But it is also contraindicated to go to extremes and try to acquire an attractive shade of the body, exhausting yourself under the merciless rays of the sun. What can happen in case of uncontrolled stay under the scorching sun?

If redness of the skin is found, this is not a sign that after a while, it will pass and a nice, chocolate tan will remain. The skin is darker due to the fact that the body produces a coloring pigment, melanin, which fights against the adverse effects of UV on our body.

Moreover, redness on the skin does not remain long, but it can lose elasticity forever. Epithelial cells may also begin to grow, visually reflected in the form of freckles and age spots, which will also remain for a long time, or even forever.

Penetrating deep into tissues, ultraviolet light can lead to ultraviolet mutagenesis, which is damage to cells at the gene level. The most dangerous can be melanoma, in case of metastasis of which death can occur.

How to protect yourself from ultraviolet radiation?

Is it possible to protect the skin from negative impact ultraviolet? Yes, if, while on the beach, you follow just a few rules:

1. It is necessary to be under the scorching sun for a short time and at strictly defined hours, when the acquired light tan acts as photoprotection of the skin.
2. Be sure to use sunscreen. Before you buy this kind of product, be sure to check if it can protect you from UV-A and UV-B.
3. It is worth including in the diet foods that contain the maximum amount of vitamins C and E, as well as rich in antioxidants.

If you are not on the beach, but have to be alone open sky, it is worth choosing special clothes that can protect the skin from UV.

Electrophthalmia - the negative effect of UV radiation on the eyes

Electrophthalmia is a phenomenon that occurs as a result of the negative effects of ultraviolet radiation on the structure of the eye. UV waves from the middle ranges in this case are very damaging to human vision.

Electrophthalmia

These events most often occur when:

• A person observes the sun, its location, without protecting the eyes with special devices;
• bright sun on open space(beach);
• The person is in a snowy area, in the mountains;
• Quartz lamps are placed in the room where the person is located.

Electrophthalmia can lead to corneal burns, the main symptoms of which are:

• Tearing of the eyes;
• Significant pain;
• Fear of bright light;
• Redness of the protein;
• Edema of the epithelium of the cornea and eyelids.

About statistics, the deep layers of the cornea do not have time to be damaged, therefore, when the epithelium heals, vision is fully restored.

How to provide first aid for electrophthalmia?

If a person is faced with the above symptoms, it is not only aesthetically unpleasant, but can also cause unimaginable suffering.

First aid is pretty simple:

• First rinse eyes with clean water;
• Then apply moisturizing drops;
• Put on glasses;

To get rid of pain in the eyes, it is enough to make a compress from wet black tea bags, or grate raw potatoes. If these methods do not help, you should immediately seek help from a specialist.

To avoid such situations, it is enough to acquire social Sunglasses. The UV-400 marking indicates that this accessory is able to protect the eyes from all UV radiation.

How is UV radiation used in medical practice?

In medicine, there is the concept of "ultraviolet starvation", which can occur in case of prolonged avoidance sunlight. In this case, unpleasant pathologies may arise, which can be easily avoided using artificial sources of ultraviolet radiation.

Their small impact is able to compensate for the lack of winter vitamin D deficiency.

In addition, such therapy is applicable in case of joint problems, skin diseases and allergic reactions.

With UV radiation, you can:

• Increase hemoglobin, but lower sugar levels;
• Normalize the work of the thyroid gland;
• Improve and eliminate problems of the respiratory and endocrine system;
• With the help of installations with ultraviolet radiation, rooms and surgical instruments are disinfected;
• UV rays have bactericidal properties, which is especially useful for patients with purulent wounds.

IMPORTANT! Always, using such radiation in practice, it is worth familiarizing yourself not only with the positive, but also with the negative aspects of their impact. It is strictly forbidden to use artificial, as well as natural UV radiation as a treatment for oncology, bleeding, stage 1 and 2 hypertension, and active tuberculosis.

• Infrared radiation- electromagnetic radiation, with a frequency in the range from 3*10^11 to 3.75*10^14 Hz.

This type of radiation is all hot bodies. The body emits infrared radiation, even if it does not glow. For example, in every house or apartment there are batteries for heating. They emit infrared radiation, although we cannot see it. As a result, the surrounding bodies are heated in the house.

Infrared waves are sometimes also called heat waves. Infrared waves are not perceived by the human eye, since the wavelength of infrared waves exceeds the wavelength of red light.

Application area infrared radiation is very wide. Often infrared radiation is used for drying vegetables, fruits, various coatings etc. There are devices that allow you to convert invisible infrared radiation into visible. Binoculars are made that see infrared radiation; with their help you can see in the dark.

Ultraviolet radiation

• Ultraviolet radiation- electromagnetic radiation, with a frequency in the range from 8*10^14 to 3*10^16 Hz.

The wavelength ranges from 10 to 380 microns. Ultraviolet radiation is also invisible to the naked human eye. To detect ultraviolet radiation, it is necessary to have a special screen that will be coated with a luminescent substance. If ultraviolet rays fall on such a screen, then at the point of contact it will begin to glow.

Ultraviolet rays are very high chemical activity. If you project a spectrum onto photographic paper in a darkened room, then after development, the paper behind the violet end of the spectrum will blacken more strongly than in the visible region of the spectrum.

As mentioned above, ultraviolet rays are invisible. But at the same time they have a destructive effect on the skin and retina of the eyes. For example, high in the mountains it is impossible to stay without clothes and dark glasses for a long time, since the ultraviolet rays directed from the Sun are not sufficiently absorbed in the atmosphere of our planet. Even ordinary glasses can protect your eyes from harmful UV radiation - glass absorbs UV rays very strongly.

However, in small doses, ultraviolet rays even helpful. They influence the central nervous system, stimulate a number of important vital functions. Under their influence, a protective pigment appears on the skin - a tan. Among other things, these rays kill various pathogenic bacteria. For this purpose, they are most often used in medicine.