What is the heatwave?
A heat wave is defined as a level of very high heat during the day and night for at least three consecutive days . The definition of a heat wave is therefore based on two parameters: heat and duration.
What are the risks associated with the heat wave?
If you are exposed to high heat for too long you risk severe fatigue , dehydration or heat stroke , see hyperthermia .
The most fragile people and those most exposed to heat are particularly at risk .
A few days after the start of summer, on June 27, in the United States and Canada, National Sunglasses Day is celebrated each year. This day was created by the Vision Council which dedicates a site to it nationalsunglassesday.com
Why a National Sunglasses Day?
This day is a simple and fun way to remind the American population of the importance of sun protection . It is necessary to protect yourself from glare, solar and UV radiation as well as the dangers associated with exposure to the sun. UV radiation (especially UVA) is harmful to the eyes and the skin, which is why it is strongly recommended to wear sunscreen to prevent burns, degeneration, cancer, etc.
During strong and long exposure, UV can cause problems in the white of the eye, keratitis, cataracts, retinal damage... In addition, sunscreens are an active anti-wrinkle! Your protected eyes are relaxed; fewer wrinkles and fine lines appear at the corner of the eyes. In addition, by blocking UV rays, your eyelids, whose skin is thin and sensitive, are protected, less risk of cancer.
Which sunglasses to choose?
Here are some tips for choosing the best sunglasses:
- Check that they provide good UV protection, 100% UV or UV400 protection
- Choose a category suited to its use: cat.4 for high mountains or sailing, cat.2 for moderately sunny weather... For summer activities, driving, cat.3 sunglasses are ideal and master key.
- Prefer a pair of comfortable sunglasses that do not slip, large and covering.
- And of course opt for nice looking glasses!
In the mountains, in winter, whether you are skiing or snowshoeing, sun protection is essential for the skin, but also for the eyes .
Effects of altitude on vision
In elevation , the reverberation increases the luminosity , which generates a significant discomfort (glare).
A cloudy sky absorbs the brightness but allows 90% of UV to pass through . As for your skin, these harmful rays can cause real "sunburn" (ophthalmia of the eyes*), but also affect the cornea (cataract) and the retina (AMD).
In fact, UV rays are less filtered by the atmosphere: the higher the altitude, the greater the amount of UV . In addition, the sun is reflected on the snow, a very reflective surface, because it reflects 80 to 95% of UV rays (while in comparison, sand only reflects 20%).
Glasses in the mountains
The choice of your glasses in the mountains:
– A curved frame , covering but ventilated (to avoid fogging).
– A lens with good optical qualities (no deformation), impact resistant, category 3 or 4 (so as not to be dazzled). There are photochromic lenses, which allow you to go from category 3 to 4, or 2 to 4. The lenses can be treated anti-reflection on the inside to eliminate dazzling reflections. Finally, one can consider the use of polarizing lenses .
– The color of the glass provides a visual effect:
Grey: for all weather
Yellow-orange: for days with dazzling sunshine
Brown: for cloudy days (increases contrast and provides better perception of relief and depth of field)
The color of the glass is not a guarantee of protection: only 100% UV protection guarantees optimal protection .
Watch out for children!
As for their skin, finer and more fragile, you have the total screen reflex, do not skip wearing glasses or a mask.
The Christmas holidays are fast approaching… Short of gift ideas?
Why not offer your loved ones, or yourself, a pair of glasses ?
It is sometimes difficult to differentiate between Ray-Ban copies and originals ! Indeed, for several years RB has been the fashionable brand that everyone is snapping up; this is why it is widely copied and reproduced to be resold on the beaches or in the various tourist markets. Through this article we will give you some tips that will be useful for you to identify a real pair of Ray-Ban .