Review of sun protection contact lenses with UV filters. What mistakes do we make when trying to protect ourselves from the sun, and how to correct them Protecting materials from UV radiation

When performing their professional duties, many specialists face the risk of splashes of biological fluids and solutions getting into their eyes. chemicals, small elements, exposure to ultraviolet radiation on the organs of vision. All of this can lead to eye infection or injury. Special safety glasses will allow you to avoid this without reducing the clarity of vision. More information about medical glasses can be obtained

Scope of application

They are most widely used in dental practice, by surgeons and laboratory assistants, protecting the eyes from:

  • particles and dust accompanying the process of sawing bones;
  • splashes of biological fluids;
  • ingress of drugs, chemical reagents;
  • radiation from photopolymerizers;
  • cleaning products and their fumes.

They will also be indispensable for dental technicians involved in the manufacture of dentures, those who work with lasers and quantum devices. Medical UV protection glasses are able to minimize the negative impact of UV lamps and irradiation devices on the eyes.

Main varieties

These products are available in several categories:

  1. Open. They touch the face only with part of the body or frame. Externally they are quite similar to sun protection models. Increased eye protection is provided by wider temples. Designed to protect against small particles and splashes. They can be additionally equipped with a light filter, protecting against IR, UV and glare radiation.
  2. Closed. They fit the entire body to the face, comprehensively protecting the eyes. Externally similar to a diving mask. Most often used when working with lasers.
  3. Helioprotective. Available in open and closed versions. They are equipped with light filters, which makes them popular when working with lasers and in dentistry. Their main task is not to transmit the blue spectrum of visible radiation emanating from the photopolymerizer.

Face shields are placed in a separate category. These screens are quite large in area, mounted on the temples, nose pads, and headband. They protect not only the eyes, but the entire face from splashes and small particles. They can be used in combination with other types of safety glasses, respirators, and masks.

Key Features

When starting to choose medical safety glasses, you should pay attention to the parameters responsible for convenience and reliability during use:

  • lenses of ordinary glasses must withstand a single impact with an energy of more than 0.6 J, and reinforced lenses - more than 1.2 J;
  • environmental friendliness of materials used in the production process;
  • the presence of softening pads in the temples and nasal arch;
  • resistance to scratches, chips, and fogging;
  • tight fit to the head even with sudden movements;
  • simplicity and efficiency of putting on/taking off;
  • the ability to individually adjust the size of the arms;
  • high visibility.

When starting to make a choice, you need to clearly know for what purposes this accessory will be used.

Rules of care

The process of caring for glasses is quite simple. They must be periodically inspected for defects, stored in a dustproof case, and cleaned and disinfected after use. If damaged, the glasses should be replaced.

Manufacturers

If you want buy safety glasses high quality and at an affordable price, we recommend paying attention to ROSOMZ products. You can see the range of products from this famous domestic manufacturer in the catalog of our website. You are guaranteed to find a model that suits your individual needs. All products have certificates of conformity and are covered by official guarantees.

2017-11-07T11:45:03+03:00

What is UV protection of polycarbonate, why is it needed and what types of it exist? It is these rather important issues that we will try to understand today.

Polycarbonate is a fairly hard, elastic and at the same time flexible material. It is used in almost all areas of construction as a translucent material. In fact, it is the strongest material among all polymers.

But polycarbonate, like polymers, has one serious drawback - it is susceptible to ultraviolet radiation. It turns out that under the influence of direct sunlight, it loses its unique abilities, becomes cloudy and becomes very fragile. Material exposed to long-term radiation is very quickly destroyed by hail, wind and even heavy rain.

UV protection polycarbonate

In the early 70s of the last century, almost everyone was faced with the problem of instability of the polycarbonate structure after prolonged exposure to solar radiation. This became problem number one. It was decided to find a way to eliminate this problem.

At the first stage, special ultraviolet stabilizers were produced and added to the primary material – granules. This was the first UV protection for polycarbonate. But this decision turned out to be quite expensive, since the cost of the final product exceeded all expectations. In addition, stabilizers did not provide 100% protection against UV radiation.

As a result, a decision was made to minimize the cost of creating ultraviolet protection for polycarbonate.

In order to avoid such problems, scientists used the developed stabilizer to create a special coating, which was applied in a fine layer to the polycarbonate. It did not transmit ultraviolet radiation and perfectly preserved the polymer from radiation. It was called ultraviolet protection or abbreviated UV protection of polycarbonate.

Types of UV protection of polycarbonate

This layer is applied to the surface of polycarbonate in two ways: spraying and extrusion.

Spraying is perhaps one of the cheapest and most unreliable methods of applying UV protection to polycarbonate. This application is reminiscent of industrial painting and is carried out immediately after the production of polycarbonate sheets. This method has serious drawbacks. First, if you are not careful, this layer is erased. Secondly, over time, this layer begins to peel off and peel off from the surface of the polycarbonate. This is not visible to the naked eye. Third, such a layer is quickly erased by microparticles during heavy winds, rain and snowfall.

Extrusion UV protection of polycarbonate is considered very practical and reliable. With this protection, the layer is applied to the surface using the extrusion method, that is, it is as if the protective layer is being implanted into the surface. This procedure occurs during the manufacture of polycarbonate panels with high temperatures. The layer of this coating is thicker than the previous one and is less susceptible to mechanical damage.

A protective film must be placed on top of the protective layer. It usually comes with brand names and inscriptions of the manufacturing company and it indicates that under the film there is UV protection of polycarbonate, or something like that. On the other side, the polycarbonate is covered with a film without inscriptions. Polycarbonate panels have only one surface with UV protection.

When installing polycarbonate, the side with UV protection should always be installed towards the radiation source, that is, the sun. Often, inexperienced installers, before installing polycarbonate sheets, remove both protective films and, when installing, inadvertently turn the side with UV protection in the opposite direction from the light source. With such an installation, even the highest quality polycarbonate will quickly become unusable, and in a year or two the first hail will turn it into a sieve.

In general, it is advisable to remove protective films after installation of the sheets; this minimizes minor mechanical damage to the surfaces. But still, if there is a need to remove them earlier, be sure to mark the side with UV protection of the polycarbonate with a marker or other method convenient for you.

Practice advice. Be sure to use during installation. If the ends of the cellular polycarbonate are covered with tapes, the expansion and contraction of the polycarbonate will be smooth without sudden jumps. This occurs due to the air gap inside the honeycomb, the principle of a double-glazed window. The air locked inside the honeycomb cannot quickly heat up or cool down. If the tapes are missing, then with a sharp expansion, for example, when the sun comes out from behind the clouds, microcracks may appear on the UV layer, which will not be visually visible, but the damage from them will be noticeable after a short period of time.

Very interesting fact . Some large polycarbonate manufacturers, such as, use primary granules to produce monolithic and cellular polycarbonate with an admixture of UV stabilizers. The volume of such stabilizers can reach up to 30% of the total volume of granules. Accordingly, such polycarbonate is not cheap, but the quality, as they say, justifies the cost. Such polycarbonates can last up to 25 years.

When choosing polycarbonate, be sure to ensure that the polycarbonate has UV protection. There are manufacturers who produce polycarbonate without UV protection.

Well, today we have discussed what UV protection of polycarbonate is, why it is needed and what types there are. In addition, tips and recommendations for installing polycarbonate were partially given. I hope this information will be useful to you.

If you have any questions or suggestions, please contact our support team or write in the comments.

You can't see, hear, or feel ultraviolet radiation, but you can actually feel its effects on your body, including your eyes.


You probably know that excessive ultraviolet exposure increases the risk of skin cancer, and you try to use protective creams. What do you know about protecting your eyes from UV radiation?
Many publications in professional publications are devoted to the study of the effects of ultraviolet radiation on the eyes, and from them, in particular, it follows that long-term exposure to it can cause a number of diseases. In the context of a decrease in the ozone layer of the atmosphere, the need for the correct selection of means of protecting the organs of vision from excess solar radiation, including its ultraviolet component, is extremely urgent.

What is ultraviolet?

Ultraviolet radiation is electromagnetic radiation invisible to the eye, occupying the spectral region between visible and X-ray radiation within the wavelength range of 100-380 nanometers. The entire region of ultraviolet radiation (or UV) is conventionally divided into near (l = 200-380 nm) and far, or vacuum (l = 100-200 nm); Moreover, the latter name is due to the fact that the radiation of this area is strongly absorbed by air and is studied using vacuum spectral instruments.


Rice. 1. Full electromagnetic spectrum of solar radiation

The main source of ultraviolet radiation is the Sun, although some sources of artificial lighting also have an ultraviolet component in their spectrum; in addition, it also occurs during gas welding work. The near range of UV rays, in turn, is divided into three components - UVA, UVB and UVC, which differ in their effect on the human body.

When exposed to living organisms, ultraviolet radiation is absorbed by the upper layers of plant tissue or the skin of humans and animals. Its biological action is based on chemical changes in biopolymer molecules caused both by their direct absorption of radiation quanta and, to a lesser extent, by interaction with the radicals of water and other low-molecular compounds formed during irradiation.

UVC is the shortest wavelength and highest energy ultraviolet radiation with a wavelength range from 200 to 280 nm. Regular exposure of living tissue to this radiation can be quite destructive, but fortunately it is absorbed by the ozone layer of the atmosphere. It should be taken into account that it is this radiation that is generated by bactericidal ultraviolet radiation sources and occurs during welding.

UVB covers the wavelength range from 280 to 315 nm and is medium-energy radiation that is hazardous to human vision. It is UVB rays that contribute to tanning, photokeratitis, and in extreme cases, cause a number of skin diseases. UVB radiation is almost completely absorbed by the cornea, but some of it, in the range of 300-315 nm, can penetrate the internal structures of the eye.

UVA is the longest wavelength and least energetic component of UV radiation with l = 315-380 nm. The cornea absorbs some UVA radiation, but most of it is absorbed by the lens. This is the component that ophthalmologists and optometrists should primarily take into account, because it is the component that penetrates deeper into the eyes than others and is potentially dangerous.

The eyes are exposed to a fairly wide range of UV radiation. Its short-wavelength part is absorbed by the cornea, which can be damaged by prolonged exposure to radiation waves with l = 290-310 nm. With increasing wavelengths of ultraviolet radiation, the depth of its penetration into the eye increases, and most of this radiation is absorbed by the lens.

The lens of the human eye is an excellent filter created by nature to protect the internal structures of the eye. It absorbs UV radiation in the range of 300 to 400 nm, protecting the retina from exposure to potentially harmful wavelengths. However, with long-term regular exposure to ultraviolet radiation, damage to the lens itself develops; over the years, it becomes yellow-brown, cloudy and, in general, unsuitable for functioning for its intended purpose (that is, cataracts form). In this case, cataract surgery is prescribed.

Light transmission of spectacle lens materials in the UV range.

Eye protection is traditionally done with the use of sunglasses, clips, shields, and hats with visors. The ability of spectacle lenses to filter out potentially dangerous components of the solar spectrum is associated with the phenomena of absorption, polarization or reflection of the radiation flux. Special organic or inorganic materials are introduced into the material of spectacle lenses or applied as coatings to their surface. The degree of protection of spectacle lenses in the UV region cannot be determined visually based on the shade or color of the spectacle lens.



Rice. 2. Ultraviolet spectrum

Although the spectral properties of spectacle lens materials are regularly discussed on the pages of professional publications, including Veko magazine, there are still persistent misconceptions about their transparency in the UV range. These incorrect judgments and ideas find their expression in the opinions of some ophthalmologists and even spill out onto the pages of mass publications. Thus, in the article “Sunglasses can provoke aggressiveness” by consultant ophthalmologist Galina Orlova, published in the St. Petersburg Vedomosti newspaper on May 23, 2002, we read: “Quartz glass does not transmit ultraviolet rays, even if it is not darkened. Therefore, any glasses with glass spectacle lenses will protect your eyes from ultraviolet radiation.” It should be noted that this is absolutely false, since quartz is one of the most transparent materials in the UV range, and quartz cuvettes are widely used to study the spectral properties of substances in the ultraviolet region of the spectrum. In the same place: “Not all plastic eyeglass lenses will protect against ultraviolet radiation.” We can agree with this statement.

In order to finally clarify this issue, let us consider the light transmission of basic optical materials in the ultraviolet region. It is known that the optical properties of substances in the UV region of the spectrum differ significantly from those in the visible region. Characteristic feature is a decrease in transparency with decreasing wavelength, that is, an increase in the absorption coefficient of most materials that are transparent in the visible region. For example, ordinary (non-spectacle) mineral glass is transparent at wavelengths above 320 nm, and materials such as uviol glass, sapphire, magnesium fluoride, quartz, fluorite, lithium fluoride are transparent in the shorter wavelength region [BSE].



Rice. 3. Light transmission of spectacle lenses made of various materials
1 - crown glass; 2, 4 - polycarbonate; 3 - CR-39 with light stabilizer; 5 - CR-39 with a UV absorber in the polymer mass

In order to understand the effectiveness of protection from UV radiation of various optical materials, let us turn to the spectral light transmission curves of some of them. In Fig. the light transmission in the wavelength range from 200 to 400 nm is presented for five spectacle lenses made of various materials: mineral (crown) glass, CR-39 and polycarbonate. As can be seen from the graph (curve 1), most mineral spectacle lenses made of crown glass, depending on the thickness at the center, begin to transmit ultraviolet radiation from wavelengths of 280-295 nm, reaching 80-90% light transmission at a wavelength of 340 nm. At the border of the UV range (380 nm), the light absorption of mineral spectacle lenses is only 9% (see table).

Material

Indicator
refraction

Absorption
UV radiation,%
CR-39 - traditional plastics
CR-39 - with UV absorber
Crown glass
Trivex
Spectralite
Polyurethane
Polycarbonate
Hyper 1.60
Hyper 1.66

This means that mineral spectacle lenses made from ordinary crown glass are unsuitable for reliable protection against UV radiation unless special additives are added to the batch for glass production. Crown glass spectacle lenses can only be used as sun filters after applying high-quality vacuum coatings.

The light transmittance of CR-39 (curve 3) corresponds to the characteristics of traditional plastics, for many years used for the production of spectacle lenses. Such spectacle lenses contain a small amount of light stabilizer that prevents photodestruction of the polymer under the influence of ultraviolet radiation and atmospheric oxygen. Traditional spectacle lenses made of CR-39 are transparent to UV radiation from 350 nm (curve 3), and their light absorption at the boundary of the UV range is 55% (see table).

We would like to draw the attention of our readers to how much better traditional plastics are in terms of UV protection compared to mineral glass.

If a special UV absorber is added to the reaction mixture, then the spectacle lens transmits radiation with a wavelength of 400 nm and is an excellent means of protection against ultraviolet radiation (curve 5). Spectacle lenses made of polycarbonate are distinguished by high physical and mechanical properties, but in the absence of UV absorbers they begin to transmit ultraviolet radiation at 290 nm (that is, similar to crown glass), reaching 86% light transmission at the boundary of the UV region (curve 2), which makes them unsuitable for use as a UV protection agent. With the introduction of a UV absorber, spectacle lenses cut off ultraviolet radiation down to 380 nm (curve 4). In table 1 also shows the light transmission values ​​of modern organic spectacle lenses made of various materials - highly refractive and with average refractive index values. All these spectacle lenses transmit light radiation starting only from the edge of the UV range - 380 nm, and reach 90% light transmission at 400 nm.

It is necessary to take into account that a number of characteristics of spectacle lenses and design features of frames affect the effectiveness of their use as means of UV protection. The degree of protection increases with increasing area of ​​spectacle lenses - for example, a spectacle lens with an area of ​​13 cm2 provides 60-65% degree of protection, and with an area of ​​20 cm2 - 96% or even more. This occurs by reducing side illumination and the possibility of UV radiation entering the eyes due to diffraction at the edges of spectacle lenses. The presence of side shields and wide temples, as well as the choice of a more curved frame shape that matches the curvature of the face, also contribute to increasing the protective properties of glasses. You should be aware that the degree of protection decreases with increasing vertex distance, since the possibility of rays penetrating under the frame and, accordingly, getting into the eyes increases.

Cutting limit

If the cutoff of the ultraviolet region corresponds to a wavelength of 380 nm (that is, light transmission at this wavelength is no more than 1%), then why do many branded sunglasses and spectacle lenses indicate a cutoff of up to 400 nm? Some experts argue that this is a marketing technique, since providing protection above the minimum requirements is more popular with buyers, and the “round” number 400 is remembered better than 380. At the same time, data has appeared in the literature about the potentially dangerous effects of light in the blue visible region spectrum to the eye, which is why some manufacturers have set a slightly larger limit of 400 nm. However, you can rest assured that 380 nm protection will provide you with sufficient UV protection to meet today's standards.

I would like to believe that we have finally convinced everyone that ordinary mineral spectacle lenses, and even more so quartz glass, are significantly inferior organic lenses in terms of ultraviolet cutting efficiency.

Prepared by Olga Shcherbakova, Veko 7/2002

Visible radiation - electromagnetic waves, perceived by the human eye, are approximately in the wavelength range from 380 (violet) to 780 nm (red). What is to the right of the visible spectrum, i.e. with a wavelength of more than 780 nm is infrared (IR) radiation, invisible to humans. To the left, i.e. with a wavelength from 250 to 400 nm, there is that part of the spectrum invisible to humans that interests us today - ultraviolet (UV). Exposure to ultraviolet radiation (UV) affects the eyes, skin and immunity. In ordinary life, direct sunlight does not reach the eyes, especially when the sun is at its zenith, but due to reflections from surfaces, it is estimated that 10-30% of the radiation (depending on external conditions) that reaches the earth's surface ends up in the eyes. In the case of paragliders, when pilots have to raise their heads towards the sun, direct rays also hit them. For winter species sports (skis, snowboarding, kite, etc.), as well as for water hobbies (kite, surfing, beaching, etc.), the amount of reflected radiation entering the eye is greater than average.

Based on wavelength, UV radiation is divided into 3 components: UVA, UVB and UVC. The shorter the wavelength, the more dangerous the radiation. UVC, the shortest wavelength and most dangerous range of ultraviolet radiation, fortunately does not reach the earth's surface thanks to the ozone layer. UVB – radiation in the range of 280-315 nm. Approximately 90% of UVB is absorbed by ozone, as well as water vapor, oxygen and carbon dioxide as sunlight passes through the atmosphere before reaching the earth's surface. UVB in small doses causes a tan, in large doses it burns and increases the chances of skin cancer. Excessive exposure of the eyes to UVB rays causes photokeratitis (sunburn of the cornea and conjunctiva, which can lead to temporary loss of vision (severe photokeratitis is often called “snow blindness”). The risk of photokeratitis increases at high altitudes, as well as in snow, if you do not protect your eyes from ultraviolet radiation. Note that the effect of ultraviolet radiation in the UVB range is limited to the surface of the eye; these ultraviolet rays practically do not penetrate into the eye.

Ultraviolet radiation in the UVA range (315-400 nm) is close to the visible spectrum, and in the same doses is less dangerous than UVB radiation. But these ultraviolet rays, unlike UVB, penetrate deeper into the eye, damaging the lens and retina. Exposure of the eyes to UVA over a long period of time leads to an increased risk of a number of dangerous diseases eyes, including cataracts and macular degeneration, which is considered the leading cause of blindness in old age. Well, let’s mention the part of the visible spectrum corresponding to the blue rays of the visible spectrum, about 400 -450 nm, (HEV “high-energy visible light”), which are directly adjacent to the long-wave part of the UV range. Long-term exposure to these high-energy visible rays is also thought to be harmful to the eyes because they penetrate deep into the eye and affect the retina.

Damaging effect ultraviolet rays depends on a number of factors:

  • Duration of stay outdoors
  • Geographic latitude of the location. The most dangerous zone is the equatorial zone
  • Altitude. The higher, the more dangerous
  • Time of day. The most dangerous time is from 10-11 a.m. to 2-4 p.m.
  • Large surfaces of water and snow that highly reflect the sun's rays

Thus, the constant effect of ultraviolet radiation on the eyes has harmful effects on the surface of the eye and its internal structures. Moreover, the negative effects have the ability to accumulate: the longer the eyes are exposed to the damaging effects of ultraviolet radiation, the higher the risk of developing pathologies of the eye structures and age-related diseases of the organ of vision.

Sunglasses are one way to limit the amount of harmful radiation reaching your eyes. Because the doses of ultraviolet radiation received over a lifetime accumulate, increasing the risk of eye disease, it is recommended to regularly wear sunglasses outdoors.

Measurements and results

Lens characteristics and concepts that we will need when analyzing tests and measurements: Optical density. This is the decimal logarithm of the ratio of the intensity of the incident radiation to the transmitted radiation. D=lg⁡(Ii/Io) That is if the optical density of the lens is 2, then it reduces the radiation intensity by 100 times, blocking 99% of the incident radiation. If D=3, then the lens blocks 99.9% of the radiation. In addition, sunglasses lenses are divided by transparency (for the visible spectrum):

  • Transparent F0, 100 - 80% light transmission used in twilight or at night, sports and safety glasses against snow and wind;
  • Light F1, 80 - 43% light transmission, glasses for cloudy weather;
  • Medium F2, 43 - 18% light transmission, used in partly cloudy weather;
  • Strong F3, 18 - 8% light transmittance, for protection from bright daylight;
  • Maximum strength F4, 8 - 3% light transmission, for maximum protection in high altitude conditions, at ski resorts, in the snowy Arctic in summer. Not intended for driving a car.

For measurements we have a spectrophotometer:

Several glasses and lenses were selected from different manufacturers at completely different prices. The cost of glasses ranged from 1 to 160 Euros (70 -11,000 rubles). So, let's start from expensive to cheap: The first 2 lenses are GloryFy, brown F2 and gray F4. Glasses of this brand with such lenses cost approximately 11,000 rubles.

Transmission graph in %, i.e. what percentage is the intensity of the transmitted radiation from the incident one:

Red shows the transmission of the brown F2 lens, and blue shows the transmission of the gray F4 lens. As can be seen from the graphs, both lenses cut all ultraviolet light well. In addition, it is clear that the brown F2 lens cuts the blue part of the spectrum much better, the gray F4 is essentially neutral (i.e. does not distort colors) and, being darker (F4 versus F2 for the brown one), darkens more strongly throughout the entire spectrum. For a more accurate assessment of how well ultraviolet radiation is blocked, here is a graph of the optical density for these lenses:

the red line is for the brown lens F2, and the blue line is for the gray lens F4

It can be seen that the optical density is greater than 2.5 over the entire ultraviolet range, i.e. More than 99% of ultraviolet light incident on the lens is blocked. To clarify, I will give the values ​​for these lenses for a wavelength of 400 nm. Optical density for gray F4 D=3.2, for brown F2 D=3.4. Or the transmittance from the incident radiation for gray F4 is 0.06%, and for brown F2 it is 0.04%.

Let's move on. Here we present graphs of transmittance and optical density for glasses in the middle price category: Smith and Tifosi - both lenses are gray, dark. The cost of glasses is about 4000-6000 rubles. And cheap glasses costing about 700 rubles - 3M and Finney - both lenses are also neutral, i.e. gray, dark. For starters, the transparency for all these mentioned lenses

From the graphs it can be seen that all lenses are category F3. In addition, it is noticeable that the lenses of cheap glasses (3M and Finney) are worse at cutting near ultraviolet light, UVA in the range of 385-400 nm. Now for all these 4 points we give the transmittance value at a wavelength of 400 nm:

  • Smith T=0.002%
  • Tifosi T=0.012%
  • Finney T=5.4%
  • 3M T=9.4% and optical density at the same wavelength:
  • Smith D=4.8
  • Tifosi D=3.9
  • Finney D=1.26
  • 3M D=1.02

It is clearly visible that cheap 3M and Finney glasses do not meet the UV400 protection requirements. They begin to protect normally from wavelengths of 385 nm and below.

But we have the cheapest glasses, unbranded (Auchan glasses). Cost 70 rubles or 1 euro. The lens is yellow, the transmission seems to be F1 category. Transparency:

Optical Density:

For a wavelength of 400 nm, the transmittance was 0.24% and the optical density was 2.62. This lens meets the UV400 requirement.

Conclusions:

It is clear that cheap glasses do not have a stable quality of protection: 2 out of 3 samples were not satisfactory. Branded glasses of the upper and middle price categories did a good job of protecting against ultraviolet radiation. In addition, when we talk about protection from ultraviolet radiation with glasses, we should take into account that light can also penetrate from the side of the frame, so, of course, glasses that cover the entire field of view and do not allow light to enter the eyes past the lenses of the glasses are better protected. And of course, when choosing glasses, you should consider how comfortable they sit on your face, because you have to wear them for hours. For people involved in active sports and frequent travelers, it is important how durable the glasses are: it’s unpleasant to find fragments in your backpack at the right time instead of glasses.

K eye Chanel. An influential woman in every way. Her every word and gesture was caught by journalists and fans. According to legend, it was with her light hand that tanning became fashionable. Returning to Paris from a cruise along the Cote d'Azur, she appeared before journalists and fans... with a tan. Which was immediately picked up as a new trend. Well, you can understand the fashionistas of the 1920s, because getting a tan was as easy as shelling pears, and they stopped drinking vinegar to make their skin pale and drawing veins on their arms with a blue pencil.

Together with visible light and thermal energy from the sun, all inhabitants of the globe are affected by ultraviolet radiation (UV).

The World Health Organization has called UV carcinogenic to humans because its role in the development of major types of skin cancer has been proven: basal cell carcinoma (basal cell carcinoma), squamous cell carcinoma and melanoma.

What is UV radiation?

The UV radiation spectrum covers wavelengths from 100 to 400 nm. Three parts of the spectrum are fundamentally different from each other:

  1. UV-C rays(length 100-280 nm) - the shortest and most powerful in impact - stops the natural barrier - the ozone layer (we will not dwell on them).
  2. UV-B rays(length 280-315 nm) – up to 90% is absorbed by ozone, water vapor, oxygen and carbon dioxide. The remaining 10%, affecting the top layer of skin, contributes to the appearance of redness and burns.
  3. UV-A rays(length 315-400 nm) - are not affected by the atmosphere and, reaching unprotected skin, can cause skin damage leading to photoaging, cancer, melanoma.

World programs for the prevention of skin cancer

What do we have today? By and large, only 3 countries in the world - Australia, Brazil and the USA - have launched large-scale educational campaigns for the prevention of skin cancer - in schools, the media, in workplaces, on beaches...

  • In Brazil, even tattooists were given a course on diagnosing skin cancer and melanoma.
  • Pragmatic Australians considered the damage caused to the treasury by excessive love of the sun. And they developed a prevention campaign at the state level, starting with cartoons for the little ones. Since 1985
  • The American Academy of Dermatology annually sponsors a national educational program teaching schoolchildren sun protection skills – Sun Wise School Program. For 30 years, a special form of screening has been carried out - examination by a dermatologist only of those individuals who have independently discovered some changes in their skin, i.e. screening through the prism of individual self-awareness. As a result of public awareness and timely contact with dermatologists, 92% of newly diagnosed melanomas had a thickness of less than 1.5 mm. And this is almost a guarantee of cure. Cures from melanoma - “Queens” of oncology!

Why is this so important on a global scale?

WHO states: 4 out of 5 cases of skin cancer can be prevented since we can prevent a significant part of the effect of UV rays.

“A good cream is expensive,” is the first thing I often hear during consultations. "The most effective means you already have!” - I say and see my eyes widening in surprise.

Effective UV protection products

1. Shadow

Shade – Just try to stay in the shade during peak sun hours! Plan your day, for example, using a mobile weather application that shows the UV index in real time: if it is >3, use a sunscreen of at least SPF 15. For example, in the standard Weather application on the iPhone, this index is on the last line of the weather characteristics.

2. Clothes

Your clothes! Look at the photo: the shirt protects better than the most modern filters.


For clothes there is UPF (Ultraviolet Protection Factor - ultraviolet protection factor), which shows how many “units” of ultraviolet light will pass through the fabric. For example, UPF 50 means one unit out of 50 will reach the skin.

As it was found out, blue and red colors clothing provides better protection than white and yellow.


Protection of dense fabrics is even more effective. In addition, the dye is also important:

Natural white linen has UPF 10; dyed with natural dyes in a dark color - UPF >50, but synthetic dyes for flax do not add protective properties.

  • Cotton:

Bleached cotton has a UPF of 4 (almost all factory whites); unbleached, naturally dyed cotton (green, brown, beige) – 46-65 UPF.

Cotton loses its properties when wet - this is due to the weaving of the threads - “holes” are formed through which drops of water can focus the sun’s rays and cause a burn. In general, experts say the protective properties of linen are better than cotton.

Lifehack: wash cotton with liquid detergent - it contains optical brightener, which, with repeated washing, will only increase the level of protection by settling on the fabric. Please note that chlorine is not an optical brightener and only worsens the protection.

What about silk? Apart from aesthetic and tactile pleasure, there is not much to count on: UPF of silk = 0. But it gains a little strength when wet - it becomes denser, but not enough to rely on it.

3. Headdress

The image will be completed - ideal, according to scientists - by a headdress - a hat with a brim of 3 inches (7.62 cm) - this will protect the face, ears, and neck.


4. Sunglasses

Sunglasses can provide up to 100% protection against UVA and UVB rays. Pay attention to the markings:

  • UV 400,
  • General,
  • High UV protection,
  • Blocks at least 80%UVB,
  • 55% UVA (must be at least 50%) -

You can safely buy such glasses.


Alas, glasses can play a cruel joke if they turn out to be not sunglasses, but simply with darkened lenses - it’s worth checking your glasses at the optics using special equipment. If there are no protective filters, the pupil will be dilated and even more damaging rays will enter the eye than if you were not wearing glasses.

By the way, the prices for sunglasses are quite affordable: a decent option can be purchased within 2,000 rubles.

5. Sunscreen

It’s just time for sunscreens.

2 mg/cm2– Manufacturers recommend applying this amount of product to areas of the body not covered by clothing. every 2 hours exposure to the sun.

Apply rather than rub in. This is fundamentally important for the formation of a continuous thick protective layer. How do we do it? Methodically, diligently rub the sunscreen from head to toe.


Important! If you apply a thin layer of cream with a high SPF, the level of protection from UVA drops more than from UVB.

Consider an example:

  • Given: Height 170 cm, weight 60 kg. Calculate the required amount of cream (the surface area of ​​the body under the swimsuit can be neglected).
  • Solution: body surface area = √170x60/3600 = 1.68 m2 = 168,000 cm2 x 2 mg = 336,000 mg = 33.6 g
  • Answer: 33.6 g. This is exactly how much you need to apply every 2 hours while in the open sun.

How much sunscreen should I apply?

Use the non-profit Australian campaign's Solar Calculator to calculate the amount of sunscreen you need based on clothing, shoes, height and weight. Simple and clear! http://www.sunsmart.com.au/suncreen-calculator/tool.asp

Or remember a simple algorithm: one teaspoon for each zone:

  • for face, neck and ears
  • for each limb
  • for the front half of the body
  • for the back half of the body
  • Total – 7 teaspoons(about 35 ml) for the entire body surface every 2 hours.

Sunscreen: myths and reality

Sunscreen is an attractive product, but there are so many myths associated with it...

Myth 1.

The higher the SPF, the better the protection!

Reality: SPF - sun protection factor - is nothing more than an indicator of the effectiveness of protection against B-rays. Protection against UVA rays is marked separately or covered under Broad spectrum - wide range protection.

Super-High SPF (>50) give a false sense of security: there is no burn (UVB rays are blocked well), and the cumulative effect of UFA will be very dramatic in the long term - “age or liver spots”, sun allergies are nothing compared to skin cancer and melanoma.

Thus, the US FDA has been fighting overstatement on the SPF label since 2007, because:

  • cream with SPF 15 already absorbs 93% of UVB rays
  • with SPF 30 - 97%
  • with SPF 50 - 98%

Moreover, such a giant as Procter & Gamble has signed up to the fact that it is almost IMPOSSIBLE in reality to comply with all test conditions in order to get the number indicated on the label!! Thank you for your honesty. In the test, only “horns and legs” remained from SPF 100 - only 37 - that’s what the manufacturer should indicate on the packaging, to be honest!

Myth 2.

Water resistance

Reality: Salt water washes off the cream within 40 minutes! Unless otherwise stated on the label. Look for time indications, for example: Water resistant 80 minutes.

Myth 3.

Substances with an anti-inflammatory effect in the composition are good:

  • licorice extract
  • daisies
  • allantoin, etc.

Reality: their effect (reduce pain, redness) can last more than 6 hours after application! You just want to soak up the sun longer - and this is already a threat of sun abuse.

Myth 4.

Physical filters - zinc and titanium oxides - are harmful to the skin

Reality: The FDA and European regulators have tested this - nanoparticles do not penetrate the skin.

Their advantages:

  • have a good balance between protection from both types of UV
  • thanks to the inert coating, they do not react when exposed to UV with the formation of free radicals
  • but when combined with Avobenzone (the best UFA filter) they reduce the effectiveness of its protection

Their disadvantages:

Titanium dioxide was recognized as a carcinogen back in 2006 - a substance that can cause a malignant process. Large doses can be obtained by inhaling sunscreen sprays with systematic use. In addition, sprays do not meet the application requirements: they are difficult to apply in an even and thick layer, so I do not recommend this form for use.

Myth 5.

Chemical filters - the best and most modern

Reality: many of them negatively affect the endocrine system

Anti-rating of chemical filters in sunscreens

1. Oxybenzone– found in 70% of sunscreens. It was originally patented as being able to reduce skin redness after sunbathing. But:

  • Estrogen-like action, has been linked to endometriosis
  • changes thyroid hormones
  • high risk of allergies
  • in animal experiments shows hormone-like activity in reproductive system and thyroid gland
  • allergy risk

3.Homosalate

  • damages estrogens, androgens, progesterone
  • its breakdown products are toxic

The above chemical filters found in breast milk breastfeeding women who used sunscreen.

In 2010, Margaret Schlumpf from the University of Zurich identified at least 1 cream “chemical” in 85% of milk samples from Swiss mothers. How does this affect the child's body? medical science unknown. And will the answer to this question be found if the same titanium dioxide, recognized as a carcinogen by the International Agency for Research on Cancer, is considered “suspicious” by Rospotrebnadzor, which does not prevent it from being one of the most popular dyes in the confectionery industry - E171 (M&Ms, Skittles, etc. ). Based on the totality of factors affecting health, it is almost impossible to identify a specific “culprit” in the occurrence of illness in a child. That's why it's so important to adhere to the principles healthy image life comprehensively.

Remember the best chemical filters in sunscreens

1. Avobenzone– the best UFA filter to date! Unstable in sunlight unless the cream contains Octisalate

2. Mexoryl SX– protects well from UFA, stable. Safe.

Excipients in sunscreens

Excipients can contribute to the reaction to sunscreen, so we read the composition of the cream:

  • Methylisothiazolinone, or MI, preservative - “Allergen of the Year 2013” ​​according to the American Contact Dermatitis Society.
  • Vitamin A(retinol palmitate) - accelerates the development of skin tumors and other diseases when applied to the skin in the presence of sunlight. That's why cosmetic procedures with vitamin A, it is recommended to move it to the evening to avoid a reaction due to direct exposure to the sun. Norwegian health authorities warn against the use of vitamin A products in pregnant and breastfeeding women.
  • Vitamins A, C and E, which are often added to cream, are unstable when heated and stored for long periods of time. This means that we protect any cream from direct sunlight and do not store it until next summer.

Some of the products that have received the best ratings from American experts and are available in Russia:

  1. Clinique Mineral Sunscreen Fluid For Face, SPF 50
  2. COOLA product line
  • COOLA Suncare Baby Mineral Sunscreen Unscented Moisturizer, SPF 50
  • COOLA Suncare Sport Mineral Sunscreen Stick, SPF 50
  • COOLA Suncare Sport Tint Mineral Sunscreen Stick, SPF 50
  1. Neutrogena product line
  • Neutrogena Sheer Zinc Dry-Touch Sunscreen, SPF 50
  • Neutrogena Sheer Zinc Face Dry-Touch Sunscreen, SPF 50
  • Neutrogena Pure & Free Baby Sunscreen, SPF 50
  • Neutrogena Sheer Zinc Dry-Touch Sunscreen, SPF 30


"Healthy tan"

Research into sunscreens is still ongoing.

Remember that a “healthy tan” is just like a “healthy” one. does not exist.

Tanning is a protective reaction of the skin to the damaging effects of ultraviolet radiation, and the best and safest protection is shade and clothing.

Useful: you can check your Sunscreen on the website http://www.ewg.org/sunscreen

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