Ultraviolet rays are a great enemy for those who are concerned about dark spots and wrinkles! You want to take proper measures on a regular basis to maintain clean skin. Therefore, we will introduce the characteristics of UV rays that you may know but do not know, and the measures you should always take care of.
Table of contents
- Characteristics of UV rays
- Points for UV protection
- Differences in the amount of UV rays depending on the weather
- UV protection is necessary even indoors!
- [Check in the video] How to make your hands and face beautiful in an instant
Characteristics of UV rays
Ultraviolet rays are roughly divided into three types, A, B, and C, depending on the length of the wavelength. We will introduce each feature.
Ultraviolet A (UV-A)
has the longest wavelength and reaches deep into the skin. It causes wrinkles and sagging.
It has the second longest wavelength after UV-B (UV-B)
and A, and reaches the upper layers of the skin, causing spots and freckles.
Ultraviolet C wave (UV-C)
・The wavelength is short, it is absorbed by the ozone layer and does not reach the surface of the earth.
Due to the above characteristics, it is “ultraviolet A wave” and “ultraviolet B wave” that you should always be careful about.
UV rays vary depending on the season and time of day, with the highest amount of UV rays in the summer. However, it gradually increases from the spring when the cherry blossoms start to bloom, and it increases explosively in early summer! By the way, the most important time of the day is from 10:00 am to 2:00 pm.
In the first place, the amount of UV rays is measured by “strength of UV rays x time”, so even if it is weak UV rays, if you continue to be exposed to it for a long time, it is the same as being exposed to strong UV rays. Regardless of the time of day or weather, it is important to take proper precautions.
Points for UV protection
So how should we deal with it? The most important point for UV protection is to apply sunscreen. There are various sunscreens in the lineup, but the point is to pay attention to “SPF” and “PA”.
・SPF (Sun Protection Factor)
“Ultraviolet protection effect”. Index to prevent ultraviolet B waves that cause spots and freckles. It is indicated by a number from 1 to 50, and the higher the number, the higher the effect.
・PA (Protection Grade of UVA)
: Four levels of “+” marks indicate the degree of effectiveness in preventing UV-A, which causes wrinkles and sagging. It ranges from + (effective) to ++++ (extremely effective).
50 is the most effective for SPF and ++++ is the most effective for PA.
If you go out in your daily life, SPF 10 or higher and PA+ or higher are sufficient, but for marine sports and leisure activities in the scorching sun, it is recommended to choose SPF 30 or higher and PA+++ or higher.
The types of sunscreens on the market include milky lotion types that are suitable for dry skin, refreshing gel types, and spray types that are easy to reapply when you go out. Don’t forget to use a sunscreen that fits your skin and reapply it frequently.
If the PA or SPF value is low, it should be reapplied every 2-3 hours, and if the value is high, it should be reapplied every 5-6 hours.
Extra sunscreen measures are also important
It is also an important point to add sunscreen and be conscious of not exposing your skin to the sun.
Even in the summer, it is more effective to wear dark-colored clothes with long sleeves and collars when walking outside, and to use accessories such as hats and sunglasses skillfully.
In addition, it would be nice to shut out the UV rays with a parasol. Sudden torrential downpours are common, so it’s a good idea to bring an umbrella that can be used for rain or shine.
Differences in the amount of UV rays depending on the weather
Many people seem to wonder, “Do I need to take measures against UV rays on cloudy days? ” You should be careful.
On cloudy days, clouds block the sun, making it harder for UV rays to reach us than on sunny days. According to the Japan Meteorological Agency, UV rays are reduced by 80 to 90% on slightly cloudy days, 60% on cloudy days, and 30% on rainy days.
However, even when there are many clouds, the sunlight from the gaps can take advantage of the scattered light, and more UV rays can fall than when the weather is clear. Just because it’s cloudy doesn’t mean you have less UV rays, so basically it’s recommended to wear sunscreen when you go out.
UV protection is necessary even indoors!
Be careful if you think, ” Is it really better to take measures against UV rays indoors? ” UV protection is not just for going out! Ultraviolet rays, even for short periods of time, can damage the skin. Of particular concern are the UV-A waves, which account for about 95% of the UV rays that reach the earth’s surface, and the UV-B waves, which have a strong effect on the skin.
“UV-A waves”, which are characterized by a long wavelength, are actually troublesome because they can pass through window glass and curtains and reach indoors. Only about 30 to 40% is cut from a single piece of window glass, and only about 30% is cut from a thin curtain.
In other words, it can be said that the UV rays that enter through windows throughout the year have a considerable adverse effect on the skin.
Indoor UV protection
The easiest way to prevent UV rays indoors is to use curtains that block light and UV rays. Even thin curtains can block UV rays, so it’s a good idea to get one if necessary.
For skylights and small windows that are difficult to attach curtains to, it is also effective to use a commercially available “UV cut film”. If you choose a colorless and transparent one, it is recommended to ensure brightness. Also, although it lacks convenience, there is also a method to make the window glass “UV cut glass”.
As for measures other than curtains and UV cut film, it is recommended to apply sunscreen quickly. For “UV-A waves”, a high PA value is sufficient, and for “UV-B waves”, an SPF value of “30” is sufficient. There are moist cream-type sunscreens, but lotion-type sunscreens with a light texture can be used indoors without hesitation.