1 Harm of ultraviolet rays
Ultraviolet rays or ultraviolet rays, UV rays are a type of electromagnetic waves with wavelengths shorter than light that the human eye can see but longer than X-rays. Ultraviolet rays cannot be seen by the naked eye.
Sources of UV rays
Most of us are exposed to natural ultraviolet radiation from the sun . However, in sunlight only about 10% is ultraviolet, 1/3 of which will penetrate the atmosphere and reach the earth. The amount of ultraviolet rays that affect the earth is 95% UVA and 5% UVB . Meanwhile, UVC rays do not affect the earth because of their short wavelength and are completely absorbed by the protective ozone layer of the earth.
Sunlight is not the only source of ultraviolet rays. Humans have also produced artificial sources of ultraviolet rays . Artificial electromagnetic wave sources are often used in UV lamps, therapeutic lamps, germicidal lamps, halogen lamps and some types of laser generators .
Hazard levels hierarchical by hour of the day
The time when the intensity of UV rays is strongest is from 10 a.m. to 2 p.m. During this time, we should minimize outdoor movement and when necessary, take measures to prevent UV rays.
UV rays reaching the ground depend on many factors such as location, altitude, time of day, time of year, and cloud cover. People evaluate the danger of UV rays through the UV index, the higher the UV index, the greater the ability to affect the body.
On extremely hot days, the UV index will be high, for example, the UV index in Hanoi and the UV index in Saigon can be up to about 10-11 and there is a high risk of harmful effects. to skin and eyes when exposed to direct sunlight.
Effects on the eyes and skin around the eyes
The harmful effects of UV rays will be most affected when exposed directly to the surface of the skin and eyes, causing many serious problems in the long run.
- For the eyes , regular exposure to UV rays has the potential to lead to keratitis, pinkeye, cataracts, retinal damage, and macular degeneration.
- The skin of the whole body in general and around the eyes in particular, if regularly exposed to sunlight without protection, UV rays will attack the dermis, making the skin dark (tanning). . In addition, intense sunlight will cause the skin to age quickly, create wrinkles, damage and even lead to skin cancer.
2 Rainy days, shady days have ultraviolet rays or not?
Never think that, on rainy or cloudy days, your skin will not be damaged by ultraviolet rays. UV rays work regardless of whether the daytime temperature is high or low, the season of the year and the time of day. They appear at all times of the day and work independently whether it is raining or sunny or shady.
3 ways to prevent harmful effects of UV rays on the eyes and skin around the eyes
Because the skin around the eyes is very sensitive, it is difficult to use sunscreen, so choose the right protective eyewear.
When going out on the street, you can use UV-blocking glasses to protect your eyes, avoiding the harmful effects of UV rays to important parts of the eye such as the cornea, lens and retina.
UV protection glasses should choose a type with large frames , the ability to hug the face, and cover the skin around the eyes to be able to block the sun.
However, you should choose glasses that suit your face, usually choose glasses that are opposite in shape to your face. For example, when you have a long face, you should choose round glasses, and vice versa.
Above is an article to help you better understand ultraviolet rays. Hopefully from the information of the article, you can choose to buy a UV-resistant glasses to protect your eyes!