That radiation from the sun can be harmful to health and that it should be protect your eyes from the sun it is a problem that many people are aware of in general terms, but they are far from being aware of all that it implies.
To illustrate this, we will give a simple figure: In the world, more than three million people a year lose their sight due to receiving excessive direct or indirect solar radiation.
To better understand the correct way to protect your eyes from the sun, in this publication we will talk about the different types of electromagnetic radiation emitted by the sun and the effects of each one on the eye.
Types of solar radiation
Depending on the wavelength of each of the solar radiations we can distinguish:
Ultraviolet Rays (UV) : invisible to the human eye and the most harmful, so they are the most necessary to protect the eyes. In turn, they are subdivided by wavelength ranges.
Ultraviolet C (UV-C) : Between 100 and 280nm. Despite being the most harmful and harmful to health, they should not worry us (at least for now) because the ozone layer is in charge of absorbing them and they do not reach the earth.
Ultraviolet B (UV-B) : Between 280 and 315nm. It is the UV radiation with the highest energy and is very harmful to the eye as it is absorbed mainly by the cornea and lens.
Ultraviolet A (UV-A) : Between 315 and 400nm. Although they have less energy than UV-B radiation, they are more penetrating and in the eye are capable of reaching the retina and damaging it and even producing cataracts . It is undoubtedly about the most harmful solar radiation for the eye and from which it is best to protect it.
- Ultraviolet C (UV-C) : Between 100 and 280nm. Despite being the most harmful and harmful to health, they should not worry us (at least for now) because the ozone layer is in charge of absorbing them and they do not reach the earth.
Visible light spectrum : are those rays of light that the human eye is capable of perceiving. It spans the wavelength range between 400 and 780nm. In this spectrum, blue light ranging from 400 to 500nm is also harmful to the retina.
- Infrared Rays : also invisible to the human eye, they have a wavelength between 700nm and 1mm. It is the radiation that generates the heat that comes from the sun and under normal conditions does not affect the eye.
Protect your eyes from the sun easily
Having a clear theory we can now explain how to protect the eyes from solar radiation. A good way to do it is with suitable sunglasses and for this they must meet a series of requirements:
- That have an ultraviolet filter: Most sunglasses (especially the cheap ones) only have a filter to block visible light. However, they do not have the ultraviolet (UV) filter, which is the more necessary of the two, since ultraviolet light is the most damaging to the eyes. The ultraviolet filter is impossible to appreciate when buying the glasses, so it is important to buy them in a professional and trustworthy establishment.
- That have a filter for visible light: This type of filter has more to do with personal needs than with purely medical issues. block visible light It helps to mitigate eye fatigue , but this type of light is the least damaging to sight. However, it is important that the glasses have both filters, so that we gain visual quality, comfort and health, which helps protect your eyes from the sun. In some cases, it is possible to purchase glasses with filters for a certain range of the visible light spectrum, such as filters for blue light that is harmful to the retina.
You should also keep in mind that the greatest danger lies in using sunglasses with a very strong filter for visible light, and that, at the same time, does not have an ultraviolet filter. Because? Because at that moment, by blocking visible light, the pupil dilates, but since ultraviolet light is not being blocked, it enters the eye to a greater extent, damaging it even more than if you were not wearing glasses.
Other information to take into account
Apart from the above, which is the main and most important thing, some other points must be taken into account to correctly protect the eyes from the sun.
- The color of the glasses lenses is not important. Depending on the color, better vision quality may be obtained with the glasses on, but for eye protection purposes, the color of the lenses is irrelevant.
- In Spain, special attention must be paid to protecting the eyes from the sun in June and July , and, above all, from 11 in the morning to 4 in the afternoon , since it is the season and the hours where the sun is in the best position to send us its ultraviolet rays.
- Even though the day is cloudy, it is important to wear sunglasses, since they clouds let through more than 90% of ultraviolet radiation.
- Sunglasses to drive should not absorb more than 20% of visible light to avoid losing visibility in closed spaces such as tunnels or shady places.
- When practicing activities on the beach, in the mountains and especially in the snow, extreme precautions should be taken as these surfaces reflect up to 80% of the UV radiation (9 new 80%, old snow 50%, white sand 30%) and can to provoke ophthalmia. The polarized lenses block this type of reflected light.
- Pay attention to the little ones in the house as they spend many hours exposed to the sun and are more vulnerable.
- Conventional glasses are not designed to protect our eyes when artificially tanned with UV light or for direct observation of eclipses solar.
- Those light skinned people with less pigment in the skin they also have less pigment in the retina and are also more vulnerable and must take extreme precautions to protect their eyes from the sun.
REMEMBER, IT IS BETTER NOT TO WEAR ANYTHING OVER YOUR EYES THAN TO WEAR POOR QUALITY GLASSES
As you see, protect your eyes from the sun it's not too complicated. By following these simple tips, your eyes will be properly protected from the sun and you will minimize the risks.