Ultraviolet radiation and its influence on the body. What infrared rays differ from ultraviolet

The sun, like other stars, radiates not only visible light - it produces a whole range of electromagnetic waves, characterized by the frequency, length and amount of portable energy. This spectrum is divided into radiation ranges to radio waves, and the most important among them is ultraviolet, without which life is impossible. Depending on the various factors, UV radiation can bring both benefits and harm.

Ultraviolet is a plot of an electromagnetic spectrum between visible and X-ray radiation and having a wavelength from 10 to 400 nm. He got such a name just because of its location - immediately over the range that is perceived by the human eye as purple color.

The ultraviolet range is measured in nanometers and is divided into subgroups in accordance with the ISO International Standard:

• middle (long-wave) - 300-400 nm;
• middle (medium-wave) - 200-300 nm;
• far (shortwave) - 122-200 nm;
• extreme - wavelength is 10-121 nm.

Depending on which group includes ultraviolet radiation, its properties may vary. Thus, the overwhelming part of the range is invisible to humans, but the near ultraviolet can be seen if it has a wavelength of 400 nm. Such violet light is emitted, for example, diodes.

Since different ranges of light differ in the amount of portable energy and frequency, the subgroups are significantly different in penetrating ability. For example, when exposed to a person, the Middle of the UV rays are blocked by the skin, and the mid-wave radiation can penetrate into the cells and cause DNA mutations. This property is used in biotechnology to obtain gennomified organisms.

As a rule, on Earth you can meet only with your neighbor and middle ultraviolet: this radiation comes from the Sun, without blocking the atmosphere, and also generated by artificially. It is the rays of 200-400 nm that play a big role in the development of life, because with their help the plant produces oxygen from carbon dioxide. Dangerous for living organisms, rigid short-wave radiation does not fall into the surface of the planet due to the ozone layer, which partially reflects and absorbs photons.

Sources of ultraviolet

Natural electromagnetic radiation generators are stars: in the process of thermonuclear synthesis occurring in the center of the star, a full range of rays is created. Accordingly, the bulk of the ultraviolet on the ground comes from the Sun. The intensity of radiation reaching the surface of the planet depends on many factors:

• the thickness of the ozone layer;
• sun height over the horizon;
• height above sea level;
• the composition of the atmosphere;
• weather;
• the reflection coefficient of radiation from the surface of the Earth.

With sunny ultraviolet associated with many myths. So, it is believed that in cloudy weather it is impossible to light up, however, at least cloudiness and affects the intensity of UV radiation, most of it is capable of penetrating through the clouds. In the mountains and winter at sea level it may seem that the risk of harm from ultraviolet is minimal, but in fact it even increases: at a high height, the radiation intensity increases due to air sparseness, and the snow cover becomes an indirect source of ultraviolet, as up to 80% Rays are reflected from him.

Especially careful need to be in a sunny, but a cold day: Even if the heat from the sun is not felt, the ultraviolet is always. Heat and UV rays are located at opposite ends of the visible spectrum and have different wavelengths. When infrared radiation in the winter passes on the tangent of land and is reflected, ultraviolet always reaches the surface.

Natural UV radiation has a significant drawback - it cannot be controlled. Therefore, artificial sources of ultraviolet radiation are developed for use in medicine, sanitation, chemistry, cosmetology and other fields. The required range of the electromagnetic spectrum is generated in them by heating the gas with an electrical discharge. As a rule, the rays are emitted by couples of mercury. This principle of action is characterized by different types of lamps:

• luminescent - additionally produce visible light due to the photoluminescence effect;
• mercut-quartz - emit waves with a length of 185 nm (hard ultraviolet) to 578 nm (orange color);
• bactericidal - have a flask made of special glass, blocking rays shorter than 200 nm, which does not allow toxic ozone;
• excilams - do not have mercury, ultraviolet is radiated in the total range;
• - Due to the effect of electroluminescence, they can work in any narrow range from to ultraviolet.

In scientific research, experiments, biotechnology use special ultraviolet. Inert gases, crystals or free electrons can be the source of radiation in them.

Thus, different artificial sources of ultraviolet generate radiation of different subtypes, which determines their scope. Lamps operating in the range of\u003e 300 nm are used in medicine,<200 - для обеззараживания и т. д.

Scope of application

Ultraviolet is able to speed up some chemical processes, for example, vitamin D synthesis in human skin, degradation of DNA molecules and polymer compounds. In addition, it causes the effect of photoluminescence in some substances. Thanks to such properties, artificial sources of this radiation are widely used in a variety of spheres.

Medicine

First of all, the medicine has found the application of the bactericidal property of ultraviolet radiation. With the help of UV rays, the growth of pathogenic microorganisms is suppressed in injuries, frostbite, burns. Blood irradiation is used in alcohol poisoning, narcotic substances and medicines, inflammation of the pancreas, sepsis, severe infectious diseases.

The irradiation of the UV lamp improves the patient's condition for diseases of various organism systems:

• endocrine - vitamin D deficiency, or rickets, diabetes;
• nervous - neuralgia of different etiology;
• muscular - myozit, osteomyelitis, osteoporosis, arthritis and other diseases of the joints;
• urinary - adnexitis;
• respiratory;
• skin diseases - psoriasis, vitiligo, eczema.

It should be borne in mind that ultraviolet is not the main means of treating the listed diseases: they are exposured as a physiotherapeutic procedure, positively affecting the patient's well-being. It has a number of contraindications, so it is impossible to apply an ultraviolet lamp without a consultation with the doctor.

UV radiation is used in psychiatry for the treatment of "winter depression", in which due to the reduction of the level of natural sunlight decreases the synthesis of melatonin and serotonin in the body, which affects the work of the central nervous system. For this, special fluorescent lamps are used, emitting a full range of light from ultraviolet to the infrared range.

Sanitation

The use of ultraviolet radiation is most useful for the purpose of disinfection. For disinfection of water, air and solid surfaces, mercury-quartz lamps of low pressure are used, generating rays with a wavelength of 205-315 nm. Such radiation is best absorbed by DNA molecules, which leads to a violation of the structure of the genes of microorganisms, which is why they cease to multiply and quickly die out.

Ultraviolet disinfection is distinguished by the lack of long-term action: immediately after the processing is completed, the effect falls, and the microorganisms begin to multiply again. On the one hand, it makes disinfection less effective, on the other - deprivates its ability to negatively affect the person. UV irradiation can not be used to complete drinking water or liquids for economic needs, but can serve as an addition to chlorination.

The irradiation with medium-wave ultraviolet is often combined with rigid radiation treatment with a wavelength of 185 nm. In this case, oxygen turns into, poisonous for pathogenic organisms. This disinfection method is called ozonation, and it has several times more efficiency than the usual lighting of the UV lamp.

Chemical analysis

Due to the fact that light with a different wavelength is absorbed in varying degrees, UV rays can be used for spectrometry - a method for determining the composition of the substance. The sample is irradiated with an ultraviolet generator with a changing wavelength, absorbs and reflects part of the rays, on the basis of which a graph-spectrum is built, unique for each substance.

The photoluminescence effect is used in the analysis of minerals, which include substances that can glow during ultraviolet irradiation. The same effect is applied to protect documents: they are marked with special paint, which emits the visible light under the black light lamp. Also with fluorescent paint, you can determine the presence of UV radiation.

Among other things, UV emitters are used in cosmetology, for example, to create a tan, drying and in other procedures, in printing and restoration, entomology, genetic engineering, etc.

Negative impact of UV rays per person

Although UV rays are widely used to treat diseases and have a wellness effect, the harmful effect of ultraviolet radiation on the human body is also. It all depends on how much energy will be transferred to alive cells with solar radiation.

The highest energy has shortwall rays (type UVC); In addition, they have the greatest penetrating ability and can destroy DNA even in deep tissues of the body. However, such radiation is completely absorbed by the atmosphere. Among the rays reaching the surface, 90% fall on the long-wavelery (UVA) and 10% - on average canol (UVB) radiation.

The prolonged effect of UVA rays or short-term irradiation UVB ultraviolet leads to a sufficiently large dose of radiation, entailing sad consequences:

• skin burns of different severity;
• mutations of skin cells, resulting in accelerating aging and melanoma;
• cataract;
• burn horny eye shell.

Delayed damage - skin and cataract cancer - can develop for a long time; In this case, the radiation of the UVA type can act at any time of the year and in any weather. Therefore, the Sun should always be protected, especially people with high photosensitivity.

Ultraviolet protection

A person has a natural protection against ultraviolet radiation - melanin contained in skin cells, hair, iris. This protein absorbs most of the ultraviolet, not allowing it to influence other structures of the body. The effectiveness of protection depends on the color of the skin, which is why the rays of UVA contribute to the occurrence of the sun.

However, with excessive exposure, Melanin stops cope with UV rays. So that the sunlight does not harm, it follows:

• try to stay in the shade;
• wearing closed clothes;
• protect eyes with special glasses or contact lenses blocking UV radiation, but transparent for visible light;
• enjoy protective creams, which include mineral or organic substances reflecting UV rays.

Of course, it is not necessary to always use a complete set of protective agents. It is necessary to focus on the ultraviolet index describing the presence of excess UV radiation at the surface of the Earth. It can take values \u200b\u200bfrom 1 to 11, and active protection is required at 8 points or more. Information about this index can be found from weather forecast.

Thus, ultraviolet is the type of electromagnetic radiation, which can bring both benefits and harm. It is important to remember that sunbathing health and rejuvenate the body only with moderate use; Excessive exposure to light can lead to serious health problems.

In agricultural production for the technological effects of optical radiation on living organisms and plants, special sources of ultraviolet (100 ... 380 nm) and infrared (780 ... 106 nm) radiation, as well as sources of photosynthetically active radiation (400 ... 700 nm) are widely used.

On the distribution of the optical radiation stream between different areas of the ultraviolet spectrum, sources of general ultraviolet (100 ... 380 nm), vital (280 ... 315 nm) and predominantly bactericidal (100 ... 280 nm) actions are distinguished.

Sources of general ultraviolet radiation - Arc mercury tubular lamps of high pressure DRT type (mercury-quartz lamps). The DRT type lamp is a quartz glass tube, in the ends of which tungsten electrodes are depressed. The lamp introduces a dosage amount of mercury and argon. For ease of attachment to the reinforcement, the DRT lamp is equipped with metal holders. DRT lamps are available with a capacity of 2330, 400, 1000 W.

Vital fluorescent lamps of type LE are made in the form of cylindrical tubes from sevel glass, the inner surface of which is covered with a thin layer of phonophore emitting in the ultraviolet region of the spectrum light stream with a wavelength of 280 ... 380 nm (maximum radiation in the region of 310 ... 320 nm). In addition to the grade of glass, the diameter of the tube and the composition of the luminofora, the tubular vital lamps are not constructively different from the tubular fluorescent low-pressure lamps and are included in the network using the same devices (throttle and starter) as the luminescent lamps of the same power. LE lamps are manufactured with a capacity of 15 and 20 W. In addition, vital-lighting fluorescent lamps have been developed.

Bactericidal lamps - These are sources of short-wave ultraviolet radiation, most of which (up to 80%) account for a wavelength of 254 nm. The design of bactericidal lamps is not fundamentally different from the tubular fluorescent low-pressure lamps, but glass with alloying additives used for their manufacture, it uses a radiation in the range of less than 380 nm. In addition, the flask of bactericidal lamps is not covered with a phosphor and has several reduced dimensions (diameter and length) compared to similar fluorescent general-purpose lamps of the same power.

Bactericidal lamps include the network using the same devices as fluorescent lamps.

Increased photosynthetically active radiation lamps. These lamps are used for artificial irradiation of plants. These include luminescent photosynthetic lamps of low pressure types of LF and LFR (R means reflex), arc mercury fluorescent photosynthetic high pressure type DRLF, metal-halide arc mercury high pressure types of DRF, DRY, droughts, DMLC, arc mercury tungsten type DRVs.

Luminescent photosynthetic lamps of low pressure types of LF and LFR in design are similar to the fluorescent low-pressure lamps and differ from them only with the composition of the phosphor, and consequently, the emission spectrum. In LF type lamps, the relatively high density of radiation lies in the wavelengths of 400 ... 450 and 600 ... 700 nm, which accounts for maximum spectral sensitivity of green plants.

DRLF lamps are structurally similar to DRL lamps, but in contrast to the latter they have increased radiation in the red part of the spectrum. Under the luminophore layer, the DRLF lamps have a reflective coating that ensures the required distribution of the radiant stream in space.

The source of infrared radiation in the simplest case can be the usual lighting lamp incandescent. In its emission spectrum, the infrared area takes almost 75%, and it is possible to increase the flow of infrared rays by a decrease in 10 ... 15% input to the stress lamp or a painting flask in blue or red. However, the main source of infrared radiation is special infrared mirror lamps.

Infrared mirror lamps (Thermal emissions) differ from ordinary paraboloid-shaped lighting lamps and lower incandescent thread temperature. The relatively low temperature of the incandescent filament of lamp thermal emissions makes it possible to shift the range of their radiation into the infrared region and increase the average burnt duration of up to 5000 hours.

The inner part of the flask of such lamps adjacent to the base is coated with a mirror layer, which allows you to redistribute and concentrate in a given direction emitted infrared flow. To reduce the intensity of visible radiation, the lower part of the flask of some infrared lamps is covered with red or blue heat-resistant varnish.

Today, the question of the potential danger of ultraviolet radiation and the most effective ways to protect the organ of vision arises.

Today, the question of the potential danger of ultraviolet radiation and the most effective ways to protect the organ of vision arises. We have prepared a list of the most common ultraviolet issues and answers to them.

What is ultraviolet radiation?

The spectrum of electromagnetic radiation is quite wide, but the person's eye is sensitive only to a certain area called visible spectrum, which covers the wavelength range from 400 to 700 nm. The radiation, which are outside the visible range, are potentially hazardous and include infrared (with waves of more than 700 nm long) and ultraviolet area (less than 400 nm). Radiations having a shorter wavelength than ultraviolet, are called X-ray and γ-radiation. If the wavelength is greater than the same indicator in infrared radiation, then it is radio waves. Thus, ultraviolet (UV) radiation is an invisible electromagnetic radiation that occups the spectral region between visible and X-ray radiation within 100-380 nm wavelengths.

What ranges has ultraviolet radiation?

As visible light can be divided into components of different colors, which we observe when the rainbow occurs, and the UV range, in turn, has three components: UV-A, UV-B and UV-C, and the latter is the most short-wave and high-energy Ultraviolet radiation with a wavelength range of 200-280 nm, but it is mainly absorbed by the upper layers of the atmosphere. UV-B-radiation has a wavelength of 280 to 315 nm and is considered to be the radiation of medium energy, which represents the danger to the human body. UV-a-radiation is the most long-wave component of the ultraviolet with a range of wavelengths 315-380 nm, which has the maximum intensity by the time the surface of the earth is achieved. UV-a-radiation penetrates biological tissue deeper, although its damaging effect is less than that of UV-B rays.

What does the name "Ultraviolet" mean?

This word means "over (above) violet" and comes from the Latin word Ultra ("over") and the names of the shortest radiation of the visible range - purple. Although UV radiation is not felt by the human eye, some animals are birds, reptiles, as well as insects, such as bees, can see in such a world. Many birds have a coloring of the sucping, which is invisible in the conditions of visible lighting, but is well distinguishable in ultraviolet. Some animals are also easier to notice in the rays of the ultraviolet band. Many fruits, flowers and seeds are perceived by the eye more clearly with such lighting.

Where does ultraviolet radiation come from?

Outdoor main source of UV radiation is the sun. As already mentioned, it is partially absorbed by the upper layers of the atmosphere. As a person rarely looks right in the sun, the main harm for the organ of vision arises as a result of the impact of scattered and reflected ultraviolet. In the premises, UV radiation occurs when using sterilizers for medical and cosmetic instruments, in solariums for the formation of a tan, in the process of applying various medical diagnostic and therapeutic instruments, as well as when curing fillings in dentistry.

In solariums, UV radiation occurs to form a tan

In industry, UV radiation is formed during welding work, and its level is so high, which can lead to serious eye damage and skin, so the use of protective agents is prescribed as mandatory for welders. Fluorescent lamps widely used for lighting at work and at home are also sources of UV radiation, but the level of the latter is very insignificant and does not represent a serious danger. Halogen lamps, which are also used for lighting, give light from the UV component. If a person is close to a halogen lamp without a protective cap or screen, then the level of UV radiation can cause serious eyes with his eyes.

In industry, UV radiation is formed during welding work, and its level is so high, which may result in serious eye damage and skin

What does the intensity of the impact of ultraviolet depend on?

Its intensity depends on many factors. First, the height of the Sun above the horizon varies depending on the time of year and day. In the summer in daytime, the intensity of UV-B-radiation is maximum. There is a simple rule: when your shadow is shorter than your height, then you risk getting 50% more such radiation.

Secondly, the intensity depends on geographic latitude: in the equatorial areas (the latitude is close to 0 °) the intensity of UV radiation is the highest - 2-3 times higher than in the north of Europe.
Thirdly, the intensity increases with an increase in height above sea level, as the atmosphere layer is reduced accordingly, capable of absorbing ultraviolet, so more than the most highly energy short-wave UV radiation reaches the ground surface.
Fourthly, the intensity of radiation affects the imperial capacity of the atmosphere: the sky seems to us blue due to the scattering of short-wave blue radiation of the visible range, and even more short-wave ultraviolet dissipates much stronger.
Fifth, the radiation intensity depends on the presence of clouds and fog. When the sky is cloudless, UV radiation reaches a maximum; Dense clouds reduce its level. However, transparent and rare clouds affect the level of UV radiation, fog water vapor can lead to an increase in the scattering of ultraviolet. The person can feel the most cold and foggy weather, but the intensity of UV radiation remains almost the same as on a clear day.

When the sky is cloudless, UV radiation reaches a maximum

Sixth, the amount of reflected ultraviolet varies depending on the type of reflective surface. So, for snow, the reflection is 90% of the incident UV radiation, for water, soil and grass - about 10%, and for sand - from 10 to 25%. This must be remembered by being on the beach.

What is the impact of ultraviolet on the human body?

Long-term and intensive effects of UV radiation can be harmful to living organisms - animals, plants and humans. Note that some insects are seen in the UV-A range, and they are an integral part of the environmental system and in any way they benefit from a person. The most famous result of the impact of ultraviolet on the human body is a tan, which is still a symbol of beauty and a healthy lifestyle. However, the long and intensive effect of UV radiation can lead to the development of skin cancer. It must be remembered that the clouds do not block ultraviolet, so the lack of bright sunlight does not mean that protection against UV radiation is not needed. The most harmful component of this radiation is absorbed by the ozone layer of the atmosphere. The fact of reducing the thickness of the latter means that in the future, protection against ultraviolet will become even more relevant. According to scientists' estimates, a decrease in the amount of ozone in the atmosphere of the Earth, only 1% will lead to an increase in skin cancer in 2-3%.

What danger of ultraviolet is for the organ of vision?

There are serious laboratory and epidemiological data that bind the duration of the effect of ultraviolet with eye diseases:, PTRIGUM, etc. Compared to a lens of an adult crystal, the child is significantly more permeable for solar radiation, and 80% of the cumulative effects of ultraviolet waves accumulate in the human body until they reach 18 -years old. The maximum susceptible to penetration of radiation lens is immediately after the birth of the baby: it skips up to 95% of the falling UV radiation. With age, the lens begins to acquire a yellow shade and becomes not so transparent. By 25 years, less than 25% of the falling ultraviolet rays reach the retina. When an attack eye is devoid of natural protection of the lens, so in such a situation it is important to use UV absorbing lenses or filters.
It should be borne in mind that a number of medical preparations have photosensitizing properties, that is, increase the consequences of the effects of ultraviolet. Optics and optometricists should have an idea of \u200b\u200bthe overall condition of the person and the drugs used to give recommendations on the use of protection tools.

What are the eye protection means?

The most effective way to protect against ultraviolet is the cover of the eye with special protective glasses, masks, shields that completely absorb UV radiation. In production, where sources of UV radiation are used, the use of such funds is mandatory. While staying outdoors in a bright sunny day, it is recommended to wear sunglasses with special lenses that are securely protected from UV radiation. Such points must have wide towers or adjacent shape to prevent radiation penetration on the side. Colorless glasses lenses can also perform this feature if additives-absorbers are entered into their composition or special surface treatment was carried out. Well adjacent sunglasses protect both direct increasing radiation and scattered and reflected from different surfaces. The efficiency of using sunglasses and recommendations for their use are determined by specifying the category of the filter, the lighting lenses correspond to the lighting lenses.

The most effective way to protect against ultraviolet is the cover of the eye with special protective glasses, masks that completely absorb UV radiation

What standards regulate the lights of the lenses of sunglasses?

Currently, regulatory documents are developed in our country and abroad, regulating the transformation of sunscreen lenses according to filter categories and their rules. In Russia, this is GOST R 51831-2001 "Sunglasses sunscreen. General technical requirements ", and in Europe - EN 1836: 2005" Personal Eye Protection - Sunglasses for General Use and Filters for Direct Observation of the Sun ".

Each type of sunscreen lenses is designed for certain light conditions and can be attributed to one of the categories of filters. There are only five of them, and they are numbered from 0 to 4. According to GOST R 51831-2001, the light transmission T,%, sunscreen lenses in the visible region of the spectrum can be from 80 to 3-8% depending on the category of filter. For UV-B-Range (280-315 nm), this indicator should not be greater than 0.1T (depending on the filter category, it can be from 8.0 to 0.3-0.8%), and for UV-A - emission (315-380 nm) - no more than 0.5T (depending on the category of filter - from 40.0 to 1.5-4.0%). At the same time, manufacturers of high-quality lenses and glasses establish more stringent requirements and guarantee the consumer to cut the ultraviolet to the wavelength of 380 nm or even up to 400 nm, as evidenced by special labeling on points of points, their packaging or accompanying documentation. It should be noted that for sunglasses lenses, the efficiency of protection against ultraviolet cannot be unambiguously determined by the degree of their darkening or the cost of points.

Is it true that ultraviolet is more dangerous if a person wears low-quality sunglasses?

This is true. In natural conditions, when a person is not wearing glasses, his eyes automatically react to excess brightness of sunlight by changing the size of the pupil. The brighter the light, the smaller the pupil, and with the proportional ratio of visible and ultraviolet radiation, this protective mechanism works very effectively. If a darkened lens is used, the lighting seems less bright and pupils increase, allowing more light to reach the eye. In the event that the lens does not ensure proper protection against ultraviolet (the amount of visible radiation decreases more than ultraviolet), the total amount of ultraviolet falling into the eye turns out to be more significant than in the absence of sunglasses. That is why painted and light-absorbing lenses should contain UV absorbers, which would reduce the amount of UV radiation in proportion to a decrease in the emission of the visible spectrum. According to international and domestic standards, the light-resistant sunscreen lenses in the UV region is regulated as proportional to the light-dependent spectrum in the visible part of the spectrum.

What optical material for spectacle lenses provides protection against ultraviolet?

Some materials for spectacled lenses provide the absorption of UV radiation due to its chemical structure. It activates photochromic lenses, which in appropriate conditions block its access to the eye. Polycarbonate contains groups absorbing radiation in the ultraviolet region, so it protects his eyes from ultraviolet. CR-39 and other organic materials for spectacled lenses in pure form (without additives) are passed some of the UV radiation, and special absorbers are administered to reliable eye protection. These components not only protect the user's eyes, providing cut off the ultraviolet to 380 nm, but also warn photocusing destruction of organic lenses and their yellowing. Mineral spectacle lenses from ordinary crown glass are unsuitable for reliable protection against UV radiation, if special additives are not introduced into the fitness for its production. Such lenses can be used as sunscreen filters only after applying high-quality vacuum coatings.

Is it true that the effectiveness of ultraviolet protection for photochromic lenses is determined by their light pulp in the activated stage?

Some users of glasses with ask a similar question, as they are worried about whether they will be reliably protected from ultraviolet on a cloudy day, when there is no bright solar radiation. It should be noted that modern photochromic lenses are absorbed from 98 to 100% UV radiation at any levels of illumination, that is, regardless of whether they are currently colorless, medium or dark painted. Thanks to this feature, photochromic lenses are suitable for users of points outdoors in various weather conditions. Currently, the number of people who begin to understand what danger represents the long-term impact of UV radiation for eye health, and many choose photochromic lenses. The latter are distinguished by high protective properties in combination with a special advantage - automatic change in light transaction depending on the level of illumination.

Is the dark color of the lenses guarantee protection against ultraviolet radiation?

By itself, the intensive coloring of sunscreen lenses does not guarantee protection against ultraviolet. It should be noted that cheap organic sunscreen lenses released under conditions of large-scale production may have a rather high level of protection. As a rule, at first a special UV absorber with raw materials for the production of lenses make colorless lenses, and then staining. To ensure the provision of UV protection for sunscreen mineral lenses is more difficult, since their glass passes more radiation than many types of polymeric materials. For guaranteed protection, it is necessary to introduce a number of additives into the composition of the mixture for the release of lenses and the use of additional optical coatings.
Painted recipe lenses are made from the corresponding colorless lenses that may have a sufficient amount of UV absorber to reliably cut off the corresponding radiation range. If lenses are needed with 100% protection against ultraviolet, the task of monitoring and ensuring such an indicator (up to 380-400 nm) is assigned to the optics of the consultant and the masters - the collector of the glasses. In this case, the introduction of UV absorbers to the surface layers of organic spectacle lenses is made according to the technology similar to the staining of the lenses in the solutions of dyes. The only exception is that UV protection does not see the eye and special devices are needed for its check - UV testers. Manufacturers and suppliers of equipment and dyes for coloring organic lenses include various formulations for surface treatment in their range, providing different levels of protection against ultraviolet and short-wave visible radiation. To control the lighting of the ultraviolet component in the conditions of the standard optical workshop is not possible.

Should I introduce absorber ultraviolet radiation into colorless lenses?

Many specialists believe that the introduction of UV absorber in colorless lenses will only benefit, as it will protect the eyes of users and warn the deterioration of the properties of the lenses under the influence of UV radiation and air oxygen. In some countries where there is a high level of solar radiation, for example in Australia, this is a mandatory. As a rule, try to reduce radiation to 400 nm. Thus, the most dangerous and high-energy components are excluded, and the remaining radiation is sufficient for the right perception of the color of the surrounding reality. If the cutting border move into a visible area (up to 450 nm), then the lenses will appear yellow, with an increase in up to 500 nm - orange.

How can you make sure that lenses provide protection against ultraviolet radiation?

Many different UV testers are represented on the optical market, which allow you to check the light-cutting lenses in the ultraviolet band. They show what level of transmission in this lenses in the UV band. However, it should be taken into account that the optical strength of the corrective lens can affect the measurement data. More accurate data can be obtained using complex instruments - spectrophotometers, which not only show light transmission at a certain wavelength, but also take into account the optical power of the corrective lens.

Protection against ultraviolet radiation is an important aspect to be taken into account when selecting new spectacled lenses. We hope that those given in this article answers to questions about ultraviolet radiation and ways to protect against it will help you choose speaking lenses that will be able to keep your eyes' health for many years.

Ultraviolet radiation in medicine is used in the optical range of 180-380 nm (integral spectrum), which is divided into a short-wave-wave area (C or Couff) - 180-280 nm, average-wave (B) - 280-315 nm and long-wave (A) - 315- 380 Nm (DUF).

Physical and physiological effect of ultraviolet radiation

Penetrates biological tissue to a depth of 0.1-1 mm, absorbed by molecules of nucleic acids, proteins and lipids, has the energy of photons sufficient for the breaking of covalent bonds, electron excitation, dissociation and ionization of molecules (photovoltaic effect), which leads to the formation of free radicals, ions, peroxide (photochemical effect), i.e. There is a sequential conversion of the energy of electromagnetic waves into the chemical energy.

UV radiation action mechanism - biophysical, humoral and nervous reflex:

Change in the electronic structure of atoms and molecules, ionic conjugation, electrical properties of cells;
- inactivation, denaturation and coagulation of protein;
- photolisis - the decay of complex protein structures - the allocation of histamine, acetylcholine, biogenic amines;
- photo oxidation - strengthening of oxidative reactions in tissues;
- photosynthesis - reparative synthesis in nucleic acids, elimination of damage to DNA;
- photoisomization - the inner regrouping of atoms in the molecule, the substances acquire new chemical and biological properties (provitamin - d2, d3),
- photosensitivity;
- Erythema, with KUF develops 1.5-2 hours, with duf - 4-24 hours;
- pigmentation;
- thermoregulation.

Ultraviolet radiation has an action on the functional state of various organs and human systems:

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

Therapeutic effect of ultraviolet radiation

The reaction from organs and systems is depending on the wavelength, dose and methods of exposure to f-radiation.

Local irradiation:

Anti-inflammatory (A, B, C);
- bactericidal (C);
- painful (A, B, C);
- epithelision, regenerating (A, B)

General irradiation:

Stimulating immunity reactions (A, B, C);
- desensitizing (A, B, C);
- Regulation of the Vitamin Balance "D", "C" and exchange processes (A, B).

Indications for UFO therapy:

Acute, subacute and chronic inflammatory process;
- injury of soft tissues and bones;
- wound;
- skin diseases;
- burn and frostbite;
- trophic ulcer;
- Rahit;
- diseases of the musculoskeletal system, joints, rheumatism;
- infectious diseases - influenza, cough, corrosive inflammation;
- pain syndrome, neuralgia, neuritis;
- bronchial asthma;
- ENT diseases - tonsillitis, otitis, allergic rhinitis, pharyngitis, laryngitis;
- Compensation of solar insufficiency, increased resistance and endurance of the organism.

Indications for ultraviolet radiation in dentistry

Diseases of the mucous membrane of the oral cavity;
- periodontal diseases;
- diseases of teeth - non-carious diseases, caries, pulpitis, periodontitis;
- inflammatory diseases of the maxillofacial region;
- Diseases of the ENCH;
- Facial pain.

Contraindications for UFO therapy:

Malignant neoplasms,
- predisposition to bleeding,
- Active tuberculosis,
- functional deficiency of the kidneys,
- hypotonic disease III stage,
- Heavy forms of atherosclerosis.
- thyrotoxicosis.

Ultraviolet radiation devices:

Integral sources using DRT lamps (arcs mercury tubular) of different power:

Orc-21m (DRT-375) - local and overall irradiation
- Windows-11M (DRT-230) - local exposure
- Lighthouse 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
- OP-2 (DRT-120) - otolaryngology, ophthalmology, dentistry.

Selective short-wave (180-280 nm) use arc bactericidal lamps (dB) in the intelligence electrical discharge mode in a mixture of mercury vapor with argon. Three types of lamps: dB-15, dB-30-1, dB-60.

Releasers are available:

Wall (ONN)
- Ceiling (ORP)
- on the tripod (OBH) and mobile (OBR)
- Local (Bod) with a DRB-8 lamp, BOP-4, OKUF-5M
- For blood irradiation (ayufok) - MD-73M "Isolde" (with LB-8 low pressure lamp).

Selective long-wavelery (310-320 nm) use luminescent erythemical lamps (LE), with a capacity of 15-30 W made of internal coating with a luminophore:

Wall Liffers (OE)
- Suspended reflected distribution (OEO)
- Mobile (OEP).

Loyage-type irradiators (EKS-2000) with an arc xenon lamp (DKS TB-2000).

Ultraviolet irradiator on a tripod (OUCH1) with a luminescent lamp (LE153), a large light ultraviolet lifter (OMA), an ultraviolet bench-top (OUN-2).

LuF-153 low pressure gas discharge lamp in Wood-1 installations, UDD-2L for PUVA and therapy, in the UV irradiator for OUC-1 limbs, for OURG-1 heads and in EDO-10 email, EGD-5. Abroad are manufactured by settings for general and local irradiation: PUVA, PSOLYLUX, PSORYMOX, VALDMAN.

Technique and technique of UFO therapy

General irradiation

Spend on one of the schemes:

Basic (from 1/4 to 3 Biodoz, adding 1/4)
- slowed down (from 1/8 to 2 biodegration, adding 1/8)
- accelerated (from 1/2 up to 4 biodoz. Adding 1/2).

Local irradiation

Exposure of the place of lesion, fields, reflexogenic zones, staged or by zones, outside. Fractional.

Features of irradiation with erytimem doses:

One skin section can be irradiated no more than 5 times, and the mucous membrane is not more than 6-8 times. Repeated irradiation of the same skin is possible only after erythema fading. The subsequent dose of irradiation is increased by 1/2-1 biodoz. In the treatment of UV rays, light-protective glasses for the patient and medical staff are used.

Dosing

The dosing of UV irradiation is carried out by determining biodosis, the biodosis is the minimum amount of UV radiation, sufficient to produce on the skin of the weak threshold erythema for the smallest time, with a fixed distance from the irradiator (20 - 100 cm). The definition of biodoxes is carried out by the BD-2 biodozetr.

Distinguish doses of ultraviolet irradiation:

Suberies (less than 1 biodoz)
- Erythemny small (1-2 biodozes)
- Middle (3-4 biodezes)
- Large (5-6 biodoxes)
- hyperacter (7-8 biodoxes)
- Massive (over 8 biodoxes).

For disinfection of air:

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

Theoretically, the question " What infrared rays differ from ultraviolet?"Could be interested in any person. After all, those and other rays are part of the solar spectrum - and we are exposed to the sun daily. In practice, it is most often asked by those who are going to acquire devices known as infrared heaters, and would like to make sure that such devices are absolutely safe for human health.

What infrared rays differ from ultraviolet in terms of physics

As you know, in addition to seven visible colors of the spectrum beyond its limits, there are also invisible radiation. In addition to infrared and ultraviolet, they include X-rays, gamma rays and microwaves.

Infrared and UV rays are similar in one: both, others relate to the part of the spectrum that does not see the unarmed eye of a person. But this is limited to their similarity.

Infrared radiation

Infrared rays were found outside the red border, between the long-wave and short-wave sections of this part of the spectrum. It is worth noting that almost half of the solar radiation is precisely infrared radiation. The main characteristic of these not visible to the eye of the rays is a strong thermal energy: all the heated bodies continuously emit it.
The radiation of this species is divided into three areas by such a parameter as the wavelength:

• from 0.75 to 1.5 microns - the near region;
• from 1.5 to 5.6 microns - average;
• from 5.6 to 100 microns - long.

It should be understood that infrared radiation is not a product of all kinds of modern technical devices, for example, IR heaters. This is a natural environment factor that is constantly acting per person. Our body continuously absorbs and gives infrared rays.

Ultraviolet radiation

The existence of rays behind the purple spectrum boundary was proven in 1801. The range of ultraviolet rays emitted by the Sun is from 400 to 20 nm, but only a small part of the short-wave spectrum reach the earth's surface - up to 290 nm.
Scientists believe that ultraviolet belongs to a significant role in the formation of the first organic compounds on Earth. However, the impact of this radiation is both negative, leading to the decay of organic substances.
When answering a question, what infrared radiation differs from ultravioletIt is necessary to consider the impact on the human body. And here the main difference is that the effect of infrared rays is limited mainly by the thermal effect, while ultraviolet rays are able to have a photochemical effect.
UV radiation is actively absorbed by nucleic acids, the consequence of changes in the most important indicators of the vital activity of cells - the ability to grow and divide. It is DNA damage is the main component of the mechanism of impact on the organisms of ultraviolet rays.
The main body of our body to which ultraviolet radiation is valid is the skin. It is known that due to UV rays, the formation process of vitamin D, which is necessary for the normal absorption of calcium, as well as serotonin and melatonin are synthesized - important hormones affecting the daily rhythms and human mood.

Impact of IR and UV radiation on the skin

When a person is exposed to sunlight, infrared and ultraviolet rays are infrared to the surface of his body. But the result of this impact will be different:

• IR rays cause blood tide to surface layers of the skin, an increase in its temperature and redness (caloric erythema). This effect disappears immediately as soon as the irradiation is terminated.
• The impact of UV radiation has a hidden period and can manifest a few hours after irradiation. The duration of ultraviolet erythema is from 10 hours to 3-4 days. The skin bluses, can peel, then coloring it becomes darker (tan).

It is proved that the excessive effect of ultraviolet can lead to malignant skin diseases. At the same time, in certain doses, UV radiation is useful for the body, which allows it to be used for prevention and treatment, as well as for the destruction of bacteria in the air of the premises.

Is infrared non-safe radiation?

Fears of people in relation to such a type of devices as infrared heaters are quite understandable. In modern society, a steady tendency with a fair fraction of fear belongs to many types of radiation: radiation, X-rays, etc.
Private consumers who are going to purchase devices based on the use of infrared radiation are most important to know the following: infrared rays are completely safe for human health. It is this worth emphasizing that considering the question what infrared rays differ from ultraviolet.
Studies have proven: long-wave IR radiation is not only useful for our body - it is absolutely necessary. With the lack of IR rays, the immunity of the body suffers, and the effect of its accelerated aging is manifested.


The positive effect of infrared radiation is no longer in doubt and manifests itself in various aspects.