Effect of UV radiation. What optical material for spectacle lenses provides UV protection? Compact emitters Crystal

UV radiation is electromagnetic waves that are invisible to the human eye. It occupies a spectral position between visible and X-ray radiation. The ultraviolet radiation interval is usually divided into near, middle and far (vacuum).

Biologists made such a division of UV rays so that they could better see the difference in the effect of rays of different lengths on a person.

• Near ultraviolet is commonly called UV-A.
• medium - UV-B,
• far - UV-C.

Ultraviolet radiation comes from the sun and the atmosphere of our planet Earth protects us from the powerful effects of ultraviolet rays. The sun is one of the few natural UV emitters. At the same time, far-ultraviolet UV-C is blocked almost completely by the Earth's atmosphere. Those 10% of long-wave ultraviolet rays reach us in the form of the sun. Accordingly, the ultraviolet that reaches the planet is mainly UV-A, and in small quantities UV-B.

One of the main properties of ultraviolet radiation is its chemical activity, due to which UV radiation has great influence on the human body. Short-wave ultraviolet radiation is considered the most dangerous for our body. Despite the fact that our planet protects us as much as possible from exposure to ultraviolet rays, if you do not take certain precautions, you can still suffer from them. Sources of short-wave radiation are welding machines and ultraviolet lamps.

Positive properties of ultraviolet light

Only in the 20th century did research begin to prove positive effects of UV radiation on the human body. The result of these studies was the identification of the following useful properties: strengthening human immunity, activating protective mechanisms, improving blood circulation, dilating blood vessels, increasing vascular permeability, increasing the secretion of a number of hormones.

Another property of ultraviolet light is its ability change carbohydrate and protein metabolism human substances. UV rays can also affect ventilation of the lungs - the frequency and rhythm of breathing, increasing gas exchange, and the level of oxygen consumption. The functioning of the endocrine system also improves; vitamin D is formed in the body, which strengthens the human musculoskeletal system.

Application of ultraviolet radiation in medicine

Quite often, ultraviolet light is used in medicine. Although ultraviolet rays can be harmful to the human body in some cases, they can also be beneficial when used correctly.

Medical institutions have long come up with useful uses for artificial ultraviolet light. There are various emitters that can help a person using ultraviolet rays cope with various diseases. They are also divided into those that emit long, medium and short waves. Each of them is used in a specific case. Thus, long-wave radiation is suitable for treating the respiratory tract, for damage to the osteoarticular apparatus, as well as in the case of various skin injuries. We can also see long-wave radiation in solariums.

Treatment performs a slightly different function mid-wave ultraviolet. It is prescribed mainly to people suffering from immunodeficiency and metabolic disorders. It is also used in the treatment of musculoskeletal disorders and has an analgesic effect.

Shortwave radiation It is also used in the treatment of skin diseases, diseases of the ears, nose, damage to the respiratory tract, diabetes, and damage to the heart valves.

In addition to various devices emitting artificial ultraviolet light, which are used in mass medicine, there are also ultraviolet lasers, having a more targeted effect. These lasers are used, for example, in eye microsurgery. Such lasers are also used for scientific research.

Application of ultraviolet in other areas

In addition to medicine, ultraviolet radiation is used in many other areas, significantly improving our lives. So, ultraviolet is excellent disinfectant, and is used, among other things, for treating various objects, water, and indoor air. Ultraviolet light is widely used and in printing: It is with the help of ultraviolet that various seals and stamps are produced, paints and varnishes are dried, and banknotes are protected from counterfeiting. In addition to its beneficial properties, when applied correctly, ultraviolet light can create beauty: it is used for various lighting effects (most often this happens at discos and performances). UV rays also help in finding fires.

One of the negative consequences ultraviolet exposure on the human body is electroophthalmia. This term refers to damage to the human organ of vision, in which the cornea of ​​the eye burns and swells, and a cutting pain appears in the eyes. This disease can occur if a person looks at the rays of the sun without special protective equipment ( sunglasses) or stays in a snowy area in sunny weather, with very bright light. Electroophthalmia can also be caused by quartzing premises.

Negative consequences can also be achieved due to long, intense exposure to ultraviolet rays on the body. There can be quite a lot of such consequences, including the development of various pathologies. The main symptoms of overexposure are

The consequences of strong radiation are the following: hypercalcemia, growth retardation, hemolysis, deterioration of immunity, various burns and skin diseases. People who constantly work outdoors, as well as those people who constantly work with devices that emit artificial ultraviolet light, are most susceptible to excessive exposure.

Unlike UV emitters used in medicine, tanning salons are more dangerous for a person. Visits to solariums are not controlled by anyone other than the person himself. People who often visit solariums in order to achieve a beautiful tan often neglect the negative effects of UV radiation, despite the fact that frequent visits to solariums can even lead to death.

The acquisition of darker skin color occurs due to the fact that our body fights the traumatic effects of UV radiation on it and produces a coloring pigment called melanin. And if redness of the skin is a temporary defect that goes away after some time, then freckles and age spots that appear on the body, which occur as a result of the proliferation of epithelial cells - permanent skin damage.

Ultraviolet light, penetrating deeply into the skin, can change skin cells at the genetic level and lead to ultraviolet mutagenesis. One of the complications of this mutagenesis is melanoma, a skin tumor. It is this that can lead to death.

To avoid the negative effects of exposure to UV rays, you need to provide yourself with some protection. At various enterprises working with devices that emit artificial ultraviolet radiation, it is necessary to use special clothing, helmets, shields, insulating screens, safety glasses, and a portable screen. People who are not involved in the activities of such enterprises need to limit themselves from excessive visits to solariums and long stays in the open sun, use sunscreens, sprays or lotions in the summer, and also wear sunglasses and closed clothing made from natural fabrics.

There are also Negative consequences from lack of UV radiation. A long-term absence of UVR can lead to a disease called “light starvation.” Its main symptoms are very similar to those of excessive exposure to ultraviolet radiation. With this disease, a person’s immunity decreases, metabolism is disrupted, fatigue, irritability, etc. appear.

Water, sunlight and oxygen contained in the earth’s atmosphere are the main conditions for the emergence and factors that ensure the continuation of life on our planet. At the same time, it has long been proven that the spectrum and intensity of solar radiation in the vacuum of space are unchanged, and on Earth the impact of ultraviolet radiation depends on many reasons: time of year, geographic location, altitude above sea level, thickness of the ozone layer, cloudiness and the level of concentration of natural and industrial impurities in the air.

What are ultraviolet rays

The sun emits rays both visible and invisible to human eye ranges. The invisible spectrum includes infrared and ultraviolet rays.

Infrared radiation is electromagnetic waves with a length of 7 to 14 nm, which carry a colossal flow of thermal energy to the Earth, and therefore they are often called thermal. The share of infrared rays in solar radiation is 40%.

Ultraviolet radiation is a spectrum electromagnetic waves, the range of which is divided conventionally into near and far ultraviolet rays. Distant or vacuum rays are completely absorbed by the upper layers of the atmosphere. Under terrestrial conditions, they are artificially generated only in vacuum chambers.

Near ultraviolet rays are divided into three subgroups of ranges:

• long – A (UVA) from 400 to 315 nm;
• medium – B (UVB) from 315 to 280 nm;
• short – C (UVC) from 280 to 100 nm.

How is ultraviolet radiation measured? Today, there are many special devices, both for domestic and professional use, that allow you to measure the frequency, intensity and magnitude of the received dose of UV rays, and thereby assess their likely harmfulness to the body.

Despite the fact that ultraviolet radiation contains sunlight occupies only about 10%, it was thanks to its influence that a qualitative leap occurred in the evolutionary development of life - the emergence of organisms from water to land.

Main sources of ultraviolet radiation

The main and natural source of ultraviolet radiation is, of course, the Sun. But man has also learned to “produce ultraviolet light” using special lamp devices:

• high-pressure mercury-quartz lamps operating in the general range of UV radiation - 100-400 nm;
• vital fluorescent lamps generating wavelengths from 280 to 380 nm, with a maximum emission peak between 310 and 320 nm;
• ozone and non-ozone (with quartz glass) bactericidal lamps, 80% of ultraviolet rays of which are at a length of 185 nm.

Both ultraviolet radiation from the sun and artificial ultraviolet light have the ability to affect the chemical structure of the cells of living organisms and plants, and at the moment, only a few species of bacteria are known that can do without it. For everyone else, the lack of ultraviolet radiation will lead to inevitable death.

So what is the real biological effect of ultraviolet rays, what are the benefits and is there any harm from ultraviolet radiation for humans?

The effect of ultraviolet rays on the human body

The most insidious ultraviolet radiation is short-wave ultraviolet radiation, since it destroys all types of protein molecules.

So why is terrestrial life possible and continuing on our planet? What layer of the atmosphere blocks harmful ultraviolet rays?

Living organisms are protected from hard ultraviolet radiation by the ozone layers of the stratosphere, which completely absorb rays in this range, and they simply do not reach the surface of the Earth.

Therefore, 95% of the total mass of solar ultraviolet comes from long waves (A), and approximately 5% from medium waves (B). But it’s important to clarify here. Despite the fact that there are many more long UV waves and they have great penetrating power, affecting the reticular and papillary layers of the skin, it is the 5% of medium waves that cannot penetrate beyond the epidermis that have the greatest biological impact.

It is mid-range ultraviolet radiation that intensively affects the skin, eyes, and also actively affects the functioning of the endocrine, central nervous and immune systems.

On the one hand, ultraviolet irradiation can cause:

• severe sunburn of the skin - ultraviolet erythema;
• clouding of the lens leading to blindness - cataracts;
• skin cancer – melanoma.

In addition, ultraviolet rays have a mutagenic effect and cause disruptions in the functioning of the immune system, which cause the occurrence of other oncological pathologies.

On the other hand, it is the effect of ultraviolet radiation that has a significant impact on the metabolic processes occurring in the human body as a whole. The synthesis of melatonin and serotonin increases, the level of which has a positive effect on the functioning of the endocrine and central nervous systems. Ultraviolet light activates the production of vitamin D, which is the main component for the absorption of calcium, and also prevents the development of rickets and osteoporosis.

Ultraviolet irradiation of the skin

Skin lesions can be both structural and functional in nature, which, in turn, can be divided into:

1. Acute injuries– arise due to high doses of solar radiation from mid-range rays received during a short time. These include acute photodermatosis and erythema.
2. Delayed damage– occur against the background of prolonged irradiation with long-wave ultraviolet rays, the intensity of which, by the way, does not depend on the time of year or the time of daylight. These include chronic photodermatitis, photoaging of the skin or solar geroderma, ultraviolet mutagenesis and the occurrence of neoplasms: melanoma, squamous cell and basal cell skin cancer. Among the list of delayed injuries is herpes.

It is important to note that both acute and delayed damage can be caused by excessive exposure to artificial sunbathing, not wearing sunglasses, as well as by visiting solariums that use uncertified equipment and/or do not carry out special preventive calibration of ultraviolet lamps.

Skin protection from ultraviolet radiation

If you do not abuse any “sunbathing”, then the human body will cope with protection from radiation on its own, because more than 20% is retained by a healthy epidermis. Today, protection from ultraviolet radiation of the skin comes down to the following techniques that minimize the risk of the formation of malignant neoplasms:

• limiting time spent in the sun, especially during midday summer hours;
• wearing light but closed clothing, because to receive the necessary dose that stimulates the production of vitamin D, it is not at all necessary to cover yourself with a tan;
• selection of sunscreens depending on the specific ultraviolet index characteristic of the area, time of year and day, as well as your own skin type.

Attention! For indigenous people middle zone In Russia, a UV index above 8 not only requires the use of active protection, but also poses a real threat to health. Radiation measurements and solar indices forecasts can be found on leading weather websites.

Exposure to ultraviolet radiation on the eyes

Damage to the structure of the eye cornea and lens (electro-ophthalmia) is possible with visual contact with any source of ultraviolet radiation. Despite the fact that a healthy cornea does not transmit and reflects hard ultraviolet radiation by 70%, there are many reasons that can become a source of serious diseases. Among them:

• unprotected observation of flares, solar eclipses;
• a casual glance at the luminary sea ​​coast or in high mountains;
• photo injury from camera flash;
• observing the operation of a welding machine or neglecting safety precautions (lack of a protective helmet) when working with it;
• long-term operation of the strobe light in discos;
• violation of the rules for visiting a solarium;
• long-term stay in a room in which quartz bactericidal ozone lamps operate.

What are the first signs of electroophthalmia? Clinical symptoms, namely redness of the eye sclera and eyelids, pain when moving the eyeballs and the sensation of a foreign body in the eye, as a rule, occur 5-10 hours after the above circumstances. However, means of protection against ultraviolet radiation are available to everyone, because even ordinary glass lenses do not transmit most UV rays.

The use of safety glasses with a special photochromic coating on the lenses, the so-called “chameleon glasses,” will be the best “household” option for eye protection. You won't have to worry about wondering what color and shade level of UV filter actually provides effective protection in specific circumstances.

And of course, if you expect eye contact with ultraviolet flashes, it is necessary to wear protective glasses in advance or use other devices that block rays harmful to the cornea and lens.

Application of ultraviolet radiation in medicine

Ultraviolet light kills fungus and other microbes in the air and on the surface of walls, ceilings, floors and objects, and after exposure to special lamps, mold is removed. People use this bactericidal property of ultraviolet light to ensure the sterility of manipulation and surgical rooms. But ultraviolet radiation in medicine is used not only to combat hospital-acquired infections.

The properties of ultraviolet radiation have found their application in a wide variety of diseases. At the same time, new techniques are emerging and constantly being improved. For example, ultraviolet blood irradiation, invented about 50 years ago, was initially used to suppress the growth of bacteria in the blood during sepsis, severe pneumonia, extensive purulent wounds and other purulent-septic pathologies.

Today, ultraviolet irradiation of blood or blood purification helps fight acute poisoning, drug overdose, furunculosis, destructive pancreatitis, obliterating atherosclerosis, ischemia, cerebral atherosclerosis, alcoholism, drug addiction, acute mental disorders and many other diseases, the list of which is constantly expanding. .

Diseases for which the use of ultraviolet radiation is indicated, and when any procedure with UV rays is harmful:

In order to live without pain, people with joint damage will benefit from an ultraviolet lamp as an invaluable aid in general complex therapy.

The influence of ultraviolet radiation in rheumatoid arthritis and arthrosis, the combination of ultraviolet therapy techniques with the correct selection of biodose and a competent antibiotic regimen is a 100% guarantee of achieving a systemic health effect with a minimal drug load.

In conclusion, we note that the positive effect of ultraviolet radiation on the body and just one single procedure of ultraviolet irradiation (purification) of the blood + 2 sessions in a solarium will help a healthy person look and feel 10 years younger.

Ultraviolet radiation is an electromagnetic wavelength between 180 and 400 nm. This physical factor has many positive effects on the human body and is successfully used to treat a number of diseases. We will talk about what these effects are, about indications and contraindications for the use of ultraviolet radiation, as well as about the devices and procedures used, in this article.

Ultraviolet rays penetrate the skin to a depth of 1 mm and cause many biochemical changes in it. There are long-wave (region A - wavelength is from 320 to 400 nm), medium-wave (region B - wavelength is 275-320 nm) and short-wave (region C - wavelength is in the range from 180 to 275 nm) ultraviolet radiation. It is worth noting that different types of radiation (A, B or C) affect the body differently, therefore they should be considered separately.

Long wave radiation

One of the main effects of this type of radiation is pigmentation: when the rays hit the skin, they stimulate the appearance of certain chemical reactions, as a result of which the pigment melanin is formed. Granules of this substance are secreted into skin cells and cause tanning. The maximum amount of melanin in the skin is determined 48-72 hours after irradiation.

The second important effect of this method of physiotherapy is immunostimulating: photodestruction products bind to skin proteins and induce a chain of biochemical transformations in cells. The result of this is the formation of an immune response after 1-2 days, that is, local immunity and nonspecific resistance of the body to many adverse environmental factors increases.

The third effect of ultraviolet irradiation is photosensitizing. A number of substances have the ability to increase the sensitivity of the skin of patients to the effects of this type of radiation and stimulate the formation of melanin. That is, taking such a drug and subsequent ultraviolet irradiation will lead to swelling of the skin and its redness (erythema) in people suffering from dermatological diseases. The result of this course of treatment will be the normalization of pigmentation and skin structure. This treatment method is called photochemotherapy.

Among the negative effects of excessive long-wave ultraviolet irradiation, it is important to mention the suppression of antitumor reactions, that is, an increase in the likelihood of developing a tumor process, in particular, melanoma - skin cancer.

Indications and contraindications

Indications for treatment with long-wave ultraviolet radiation are:

• chronic inflammatory processes in the respiratory system;
• diseases of the osteoarticular system of inflammatory nature;
• frostbite;
• burns;
• skin diseases - psoriasis, mycosis fungoides, vitiligo, seborrhea and others;
• wounds that are difficult to treat;
• trophic ulcers.

For some diseases, the use of this method of physiotherapy is not recommended. Contraindications are:

• acute inflammatory processes in the body;
• severe chronic renal and liver failure;
• individual hypersensitivity to ultraviolet radiation.

Devices

Sources of UV rays are divided into integral and selective. Integral ones emit UV rays of all three spectra, while selective ones emit only region A or regions B + C. As a rule, selective radiation is used in medicine, which is obtained using a LUF-153 lamp in irradiators UUD-1 and 1A, OUG-1 (for the head), OUK-1 (for the limbs), EGD-5, EOD-10, PUVA , Psorymox and others. Long-wave UV radiation is also used in solariums designed to obtain an even tan.

This type of radiation can affect the entire body or any part of it at once.

If the patient is undergoing general radiation, he should undress and sit quietly for 5-10 minutes. No creams or ointments should be applied to the skin. The whole body is exposed at once or its parts in turn - it depends on the type of installation.

The patient is at a distance of at least 12-15 cm from the device, and his eyes are protected with special glasses. The duration of irradiation directly depends on the type of skin pigmentation - there is a table with irradiation schemes depending on this indicator. The minimum exposure time is 15 minutes, and the maximum is half an hour.

Mid-wave ultraviolet radiation

This type of UV radiation has the following effects on the human body:

• immunomodulatory (in suberythemal doses);
• vitamin-forming (promotes the formation of vitamin D 3 in the body, improves the absorption of vitamin C, optimizes the synthesis of vitamin A, stimulates metabolism);
• anesthetic;
• anti-inflammatory;
• desensitizing (the body's sensitivity to the products of photodestruction of proteins decreases - in erythemal doses);
• trophostimulating (stimulates a number of biochemical processes in cells, as a result of which the number of functioning capillaries and arterioles increases, blood flow in tissues improves - erythema is formed).

Indications and contraindications

Indications for the use of mid-wave ultraviolet radiation are:

• inflammatory diseases of the respiratory system;
• post-traumatic changes in the musculoskeletal system;
• inflammatory diseases of bones and joints (arthritis, arthrosis);
• vertebrogenic radiculopathy, neuralgia, myositis, plexitis;
• sun fasting;
• metabolic diseases;
• erysipelas.

Contraindications are:

• individual hypersensitivity to UV rays;
• hyperfunction of the thyroid gland;
• chronic renal failure;
• systemic connective tissue diseases;
• malaria.

Devices

Radiation sources of this type, like the previous one, are divided into integral and selective.

Integral sources are lamps of the DRT type of various powers, which are installed in irradiators OKN-11M (quartz tabletop), ORK-21M (mercury-quartz), UGN-1 (for group irradiation of the nasopharynx), OUN 250 (tabletop). Another type of lamp - DRK-120 is intended for cavity irradiators OUP-1 and OUP-2.

The selective source is the LZ 153 fluorescent lamp for the OUSH-1 (on a tripod) and OUN-2 (tabletop) irradiators. Erythema lamps LE-15 and LE-30, made of glass that transmits UV rays, are also used in wall-mounted, pendant and mobile irradiators.

Ultraviolet irradiation is dosed, as a rule, using a biological method, which is based on the ability of UV rays to cause redness of the skin after irradiation - erythema. The unit of measurement is 1 biodose (the minimum time of ultraviolet irradiation of the patient’s skin on any part of his body, causing the appearance of the least intense erythema during the day). Gorbachev's biodosimeter has the form of a metal plate on which there are 6 rectangular holes that are closed with a shutter. The device is fixed on the patient’s body, UV radiation is directed at it, and every 10 seconds one window of the plate is opened alternately. It turns out that the skin under the first hole is exposed to radiation for 1 minute, and under the last - only 10 s. After 12-24 hours, threshold erythema occurs, which determines the biodose - the time of exposure to UV radiation on the skin under this hole.

The following types of doses are distinguished:

• suberythemal (0.5 biodose);
• small erythema (1-2 biodoses);
• medium (3-4 biodoses);
• high (5-8 biodoses);
• hypererythemal (more than 8 biodoses).

Methodology of the procedure

There are 2 methods – local and general.

Local exposure is carried out on a skin area the area of ​​which does not exceed 600 cm 2 . As a rule, erythemal doses of radiation are used.

The procedure is carried out once every 2-3 days, each time increasing the dose by 1/4-1/2 from the previous one. One area can be exposed no more than 3-4 times. A repeat course of treatment is recommended for the patient after 1 month.

During general exposure, the patient is in a supine position; the surfaces of his body are irradiated alternately. There are 3 treatment regimens - basic, accelerated and slow, according to which the biodose is determined depending on the procedure number. The course of treatment is up to 25 irradiations and can be repeated after 2-3 months.

Electroophthalmia

This term is called negative impact radiation of the mid-wave spectrum on the organ of vision, which consists in damage to its structures. This effect can occur when observing the sun without using protective devices, while staying in a snowy area or in very bright, sunny weather at sea, as well as during quartzing of premises.

The essence of electroophthalmia is a burn of the cornea, which is manifested by severe lacrimation, redness and cutting pain in the eyes, photophobia and swelling of the cornea.

Fortunately, in the vast majority of cases this condition is short-lived - as soon as the epithelium of the eye heals, its functions will be restored.

To alleviate your condition or the condition of those around you with electroophthalmia, you should:

• rinse eyes with clean, preferably running water;
• drip moisturizing drops into them (preparations such as artificial tears);
• wear safety glasses;
• if the patient complains of pain in the eyes, you can alleviate his suffering with the help of compresses made from grated raw potatoes or black tea bags;
• If the above measures do not give the desired effect, you should seek help from a specialist.

Shortwave radiation

It has the following effects on the human body:

• bactericidal and fungicidal (stimulates a number of reactions, as a result of which the structure of bacteria and fungi is destroyed);
• detoxification (under the influence of UV radiation, substances appear in the blood that neutralize toxins);
• metabolic (during the procedure, microcirculation improves, as a result of which organs and tissues receive more oxygen);
• correcting blood clotting ability (with UV irradiation of blood, the ability of red blood cells and platelets to form blood clots changes, and coagulation processes are normalized).

Indications and contraindications

The use of short-wave ultraviolet radiation is effective for the following diseases:

• skin diseases (psoriasis, neurodermatitis);
• erysipelas;
• rhinitis, tonsillitis;
• otitis;
• wounds;
• lupus;
• abscesses, boils, carbuncles;
• osteomyelitis;
• rheumatic heart valve disease;
• essential hypertension I-II;
• acute and chronic respiratory diseases;
• diseases of the digestive system (peptic ulcer of the stomach and duodenum, gastritis with high acidity);
• diabetes;
• long-term non-healing ulcers;
• chronic pyelonephritis;
• acute adnexitis.

Contraindication to this species treatment is individual hypersensitivity to UV rays. Blood irradiation is contraindicated for the following diseases:

• mental illnesses;
• chronic renal and liver failure;
• porphyria;
• thrombocytopenia;
• callous ulcer of the stomach and duodenum;
• decreased blood clotting ability;
• strokes;
• myocardial infarction.

Devices

Integrated radiation sources - DRK-120 lamp for cavity irradiators OUP-1 and OUP-2, DRT-4 lamp for nasopharynx irradiator.

Selective sources are bactericidal lamps DB of varying power - from 15 to 60 W. They are installed in irradiators of the OBN, OBS, OBP types.

In order to carry out autotransfusions of ultraviolet irradiated blood, the MD-73M “Isolda” device is used. The radiation source in it is the LB-8 lamp. It is possible to regulate the dose and area of ​​irradiation.

Methodology of the procedure

The affected areas of the skin and mucous membranes are exposed to general UV irradiation schemes.

For diseases of the nasal mucosa, the patient is in a sitting position on a chair, with his head slightly thrown back. The emitter is inserted to a shallow depth alternately into both nostrils.

When irradiating the tonsils, a special mirror is used. Reflecting from it, the rays are directed to the left and right tonsils. The patient's tongue is stuck out and he holds it with a gauze pad.

The effects are dosed by determining the biodose. In acute conditions, start with 1 biodose, gradually increasing it to 3. You can repeat the course of treatment after 1 month.

The blood is irradiated for 10-15 minutes over 7-9 procedures with a possible repeat of the course after 3-6 months.

The concept of ultraviolet rays was first encountered by an Indian philosopher of the 13th century in his work. The atmosphere of the area he described Bhootakasha contained violet rays that cannot be seen with the naked eye.

Soon after infrared radiation was discovered, the German physicist Johann Wilhelm Ritter began searching for radiation at the opposite end of the spectrum, with a wavelength shorter than that of violet. In 1801, he discovered that silver chloride, which decomposes faster when exposed to light decomposes under the influence of invisible radiation outside the violet region of the spectrum. Silver chloride white within a few minutes it darkens in the light. Different parts of the spectrum have different effects on the rate of darkening. This happens most quickly in front of the violet region of the spectrum. Many scientists, including Ritter, then agreed that light consists of three distinct components: an oxidative or thermal (infrared) component, an illuminant (visible light) component, and a reducing (ultraviolet) component. At that time, ultraviolet radiation was also called actinic radiation. Ideas about the unity of three various parts spectrum were first voiced only in 1842 in the works of Alexander Becquerel, Macedonio Melloni and others.

Subtypes

Degradation of polymers and dyes

Scope of application

Black light

Chemical analysis

UV spectrometry

UV spectrophotometry is based on irradiating a substance with monochromatic UV radiation, the wavelength of which changes over time. The substance absorbs UV radiation at different wavelengths to varying degrees. A graph, the ordinate axis of which shows the amount of transmitted or reflected radiation, and the abscissa axis the wavelength, forms a spectrum. The spectra are unique for each substance, which is the basis for the identification of individual substances in a mixture, as well as their quantitative measurement.

Mineral Analysis

Many minerals contain substances that, when illuminated by ultraviolet light, begin to emit visible light. Each impurity glows in its own way, which makes it possible to determine the composition of a given mineral by the nature of the glow. A. A. Malakhov in his book “Interesting about Geology” (Moscow, “Young Guard”, 1969. 240 pp) talks about it this way: “An unusual glow of minerals is caused by cathode, ultraviolet, and x-rays. In the world of dead stone, those minerals that light up and shine most brightly are those that, once in the zone of ultraviolet light, tell about the smallest impurities of uranium or manganese included in the rock. Many other minerals that do not contain any impurities also flash a strange “unearthly” color. I spent the whole day in the laboratory, where I observed the luminescent glow of minerals. Ordinary colorless calcite became miraculously colored under the influence of various light sources. Cathode rays made the crystal ruby ​​red; in ultraviolet light it lit up with crimson-red tones. The two minerals, fluorite and zircon, were indistinguishable in X-rays. Both were green. But as soon as the cathode light was connected, the fluorite became purple, and the zircon turned lemon yellow.” (p. 11).

Qualitative chromatographic analysis

Chromatograms obtained by TLC are often viewed under ultraviolet light, which makes it possible to identify a number of organic substances by their glow color and retention index.

Catching insects

Ultraviolet radiation is often used when catching insects with light (often in combination with lamps emitting in the visible part of the spectrum). This is due to the fact that for most insects the visible range is shifted compared to human vision, in the short-wave part of the spectrum: insects do not see what humans perceive as red, but they see soft ultraviolet light.

Artificial tanning and “Mountain sun”

At certain dosages, artificial tanning can improve the condition and appearance of human skin and promotes the formation of vitamin D. Fotaria are currently popular, which in everyday life are often called solariums.

Ultraviolet in restoration

One of the main tools of experts is ultraviolet, x-ray and infrared radiation. Ultraviolet rays make it possible to determine the aging of a varnish film - fresher varnish looks darker in ultraviolet light. In the light of a large laboratory ultraviolet lamp, restored areas and hand-written signatures appear as darker spots. X-rays are retained by the heaviest elements. In the human body this is bone tissue, but in a painting it is whitewash. The basis of white in most cases is lead; in the 19th century, zinc began to be used, and in the 20th century, titanium. All these are heavy metals. Ultimately, on film we get an image of the whitewash underpainting. Underpainting is the individual “handwriting” of the artist, an element of his own unique technology. To analyze the underpainting, a database of X-ray photographs of paintings by great masters is used. These photographs are also used to determine the authenticity of a painting.

Notes

1. ISO 21348 Process for Determining Solar Irradiances. Archived from the original on June 23, 2012.
2. Bobukh, Evgeniy On animal vision. Archived from the original on November 7, 2012. Retrieved November 6, 2012.
3. Soviet encyclopedia
4. V. K. Popov // UFN. - 1985. - T. 147. - P. 587-604.
5. A. K. Shuaibov, V. S. Shevera Ultraviolet nitrogen laser at 337.1 nm in frequent repetition mode // Ukrainian Physical Journal. - 1977. - T. 22. - No. 1. - P. 157-158.
6. A. G. Molchanov

Ultraviolet radiation in medicine is used in the optical range of 180-380 nm (integral spectrum), which is divided into short-wave region (C or AF) - 180-280 nm, medium-wave (B) - 280-315 nm and long-wave (A) - 315- 380 nm (DUV).

Physical and physiological effects of ultraviolet radiation

Penetrates into biological tissues to a depth of 0.1-1 mm, is absorbed by molecules of nucleic acids, proteins and lipids, has photon energy sufficient to rupture covalent bonds, electronic excitation, dissociation and ionization of molecules (photoelectric effect), which leads to the formation of free radicals, ions, peroxides (photochemical effect), i.e. there is a consistent conversion of the energy of electromagnetic waves into chemical energy.

The mechanism of action of UV radiation is biophysical, humoral and neuro-reflex:

Changes in the electronic structure of atoms and molecules, ionic configuration, electrical properties of cells;
- inactivation, denaturation and coagulation of protein;
- photolysis - breakdown of complex protein structures - release of histamine, acetylcholine, biogenic amines;
- photooxidation - increased oxidative reactions in tissues;
- photosynthesis - reparative synthesis in nucleic acids, elimination of damage in DNA;
- photoisomerization - internal rearrangement of atoms in a molecule, substances acquire new chemical and biological properties (provitamin - D2, D3),
- photosensitivity;
- erythema, with CUF it develops within 1.5-2 hours, with DUF - 4-24 hours;
- pigmentation;
- thermoregulation.

Ultraviolet radiation affects the functional state of various human organs and systems:

Leather;
- central and peripheral nervous system;
- autonomic nervous system;
- the cardiovascular system;
- blood system;
- hypothalamus-pituitary-adrenal glands;
- endocrine system;
- all types of metabolism, mineral metabolism;
- respiratory organs, respiratory center.

The healing effect of ultraviolet radiation

The reaction from organs and systems depends on the wavelength, dose and method of exposure to UV radiation.

Local irradiation:

Anti-inflammatory (A, B, C);
- bactericidal (C);
- painkiller (A, B, C);
- epithelializing, regenerating (A, B)

General exposure:

Stimulating immune reactions (A, B, C);
- desensitizing (A, B, C);
- regulation of vitamin balance “D”, “C” and metabolic processes (A, B).

Indications for UV therapy:

Acute, subacute and chronic inflammatory process;
- trauma to soft tissues and bones;
- wound;
- skin diseases;
- burns and frostbite;
- trophic ulcer;
- rickets;
- diseases of the musculoskeletal system, joints, rheumatism;
- infectious diseases - influenza, whooping cough, erysipelas;
- pain syndrome, neuralgia, neuritis;
- bronchial asthma;
- ENT diseases - tonsillitis, otitis, allergic rhinitis, pharyngitis, laryngitis;
- compensation for solar deficiency, increasing the stamina and endurance of the body.

Indications for ultraviolet irradiation in dentistry

Diseases of the oral mucosa;
- periodontal diseases;
- dental diseases - non-carious diseases, caries, pulpitis, periodontitis;
- inflammatory diseases of the maxillofacial area;
- TMJ diseases;
- facial pain.

Contraindications to UV therapy:

Malignant neoplasms,
- predisposition to bleeding,
- active tuberculosis,
- functional kidney failure,
- hypertension Stage III,
- severe forms of atherosclerosis.
- thyrotoxicosis.

Ultraviolet radiation devices:

Integrated sources using DRT (mercury arc tube) lamps of various powers:

ORK-21M (DRT-375) - local and general irradiation
- OKN-11M (DRT-230) - local irradiation
- Mayachnye OKB-ZO (DRT-1000) and OKM-9 (DRT-375) - group and general irradiation
- ON-7 and UGN-1 (DRT-230). OUN-250 and OUN-500 (DRT-400) - local irradiation
- OUP-2 (DRT-120) - otolaryngology, ophthalmology, dentistry.

Selective short-wave (180-280 nm) use bactericidal arc lamps (BA) in the glow electric discharge mode in a mixture of mercury vapor and argon. Lamps of three types: DB-15, DB-30-1, DB-60.

Irradiators are produced:

Wall mounted (OBN)
- ceiling (OBP)
- on a tripod (OBSh) and mobile (OBP)
- local (BOD) with lamp DRB-8, BOP-4, OKUF-5M
- for blood irradiation (AUFOK) - MD-73M "Isolde" (with low pressure lamp LB-8).

Selective long-wave (310-320 nm) use fluorescent erythema lamps (LE), 15-30 W, made of uveolian glass with an internal phosphor coating:

Wall-mounted irradiators (OE)
- suspended reflected distribution (OED)
- mobile (OEP).

Beacon-type irradiators (EOKS-2000) with a xenon arc lamp (DKS TB-2000).

An ultraviolet irradiator on a tripod (OUSH1) with a fluorescent lamp (LE153), a large beacon ultraviolet irradiator (OMU), a tabletop ultraviolet irradiator (OUN-2).

Low pressure gas discharge lamp LUF-153 in the UUD-1, UDD-2L units for Puva and therapy, in the UV irradiator for the limbs OUK-1, for the head OUG-1 and in the irradiators EOD-10, EGD-5. Units for general and local irradiation are produced abroad: Puva, Psolylux, Psorymox, Valdman.

Technique and methodology of ultraviolet therapy

General exposure

Carry out according to one of the following schemes:

Main (from 1/4 to 3 biodoses, adding 1/4 each)
- slow (from 1/8 to 2 biodoses, adding 1/8 each)
- accelerated (from 1/2 to 4 biodoses, adding 1/2 at a time).

Local irradiation

Irradiation of the affected area, fields, reflexogenic zones, staged or by zone, extrafocal. factional.

Features of irradiation with erythemal doses:

One area of ​​skin can be irradiated no more than 5 times, and the mucous membrane - no more than 6-8 times. Repeated irradiation of the same area of ​​skin is possible only after the erythema has subsided. The subsequent radiation dose is increased by 1/2-1 biodose. When treating with UV rays, light-protective glasses are used for the patient and medical staff.

Dosing

Dosing of UV irradiation is carried out by determining the biodose, biodose - minimal amount UV radiation sufficient to produce the weakest threshold erythema on the skin in the shortest time, with a fixed distance from the irradiator (20 - 100 cm). The biodose is determined using a BD-2 biodosimeter.

There are different doses of ultraviolet radiation:

Suberythemal (less than 1 biodose)
- erythema small (1-2 biodoses)
- medium (3-4 biodoses)
- large (5-6 biodoses)
- hypererythemal (7-8 biodoses)
- massive (over 8 biodoses).

For air disinfection purposes:

Indirect radiation for 20-60 minutes, in the presence of people,
- direct radiation for 30-40 minutes, in the absence of people.