Home Tech What Is UV Index? How To Check UV Index

What Is UV Index? How To Check UV Index

Have you noticed how on some days you get sunburns only after being exposed to the sun for a short time, while on other days it takes much longer for that to happen?

Do you want to learn how to better protect your skin from harmful radiation coming from the sun? To do this, you need to answer the question: what is UV index?

Knowing what UV index is, and how it relates to protecting your skin is the aim of this article. I will explain not only what the UV index is, but how you can check it on your devices and what protective and preventive measures you can take for your skin.

What is UV Index: An Introduction

The UV index stands for ultraviolet index. It is the standard of measurement of ultraviolet radiation in a particular place. To better appreciate what UV index is, we need to know what ultraviolet rays are.

What Is UV Radiation?

Light is not the only thing that the sun releases to the earth. There are several other kinds of radiation and subatomic particles released by the sun every second, one of which is ultraviolet (UV) radiation. The ozone layer prevents many of the harmful rays from reaching the earth.

What Is UV Index
When it comes to sun protection, we need to think UV, not heat!

Ultraviolet rays are a type of electromagnetic wave which means they travel at the same speed as light. The difference is that they have a higher frequency than light. These higher frequency rays can be dangerous to the human skin—and the body in general. There are three kinds of UV radiation:

UVA: These have a wavelength of between 320 and 400nanometers. They are the mildest kind of UV rays. They cause the melanin pigment to darken, creating a tan. They have limited power to cause erythema (skin burn)

UVB: With wavelengths of 280-320nanometers, they are more powerful than UVA. This kind of UV ray is associated with sunburns. They are also necessary for the production of vitamin D in the skin and increased melanin production.

UVC: With wavelengths of 200-280 nanometers, it is a good thing that they are to a very large extent prevented from reaching the earth’s surface by the atmosphere. This is because a short exposure can lead to severe sunburn, and is harmful to the eyes.

UV radiation at a low level is not dangerous and can even be beneficial, but at high levels it is dangerous. That is why we address the question what is UV index?

Does UV Radiation Affect All Skins Equally?

The simple answer to that question is no. Light skin suffers more damage than darker skin. It is easier for the rays to penetrate lighter skin, causing damage to the lower layers of the epidermis.

Understanding Ultraviolet UV Radiation and its Effects

Making Sense Of The UV Index

The UV index is calculated based on several factors such as what time of day it is, the sun’s intensity at that place, cloud cover, what angle the sun is hitting the earth at, and so forth.

The index goes from 0 (minimal risk) to 11+ (high risk). A UV index of 0-2 means most people can be under the sun for up to an hour without protection. At a higher index of 6-7, you can only stay about 20 minutes before experiencing sunburn.

The UV index changes from time to time, for instance, early in the morning, the UV index is usually between 0-2, while at midday when the sun is directly overhead, the UV index is between 7-11+.

The index is basically a measure of how long it would take for someone with “type 2” fair skin to experience sunburn. So, knowing what is UV index can also help you get adequate protection for your skin type as shall be discussed later in this article.

How To Check UV Index

Now that you know what the UV index is, we can now find out how to check the UV index. Luckily you don’t need to carry around a heavy meter to measure for UV radiation where you go. With your phone or smartwatch, you can find out the UV Index for your location. I will now proceed to mention different ways you can do that.

1. Apple Weather App

Your iPad and iPhones make it easy to check the UV Index using their Weather App. The app comes preinstalled on devices using iOS.

Open your Weather app to your current location and scroll to the bottom of the screen. You will find the UV index for your current location.

What Is UV Index

2. Apple Watch

What Is UV Index 1

Your Apple watches also come with the capability of displaying the UV index. The infographic watch face displays the UV index also, so you can know the UV index of wherever you are.

3. Google Weather App

Though Android devices do not have a dedicated weather app like iOS devices, finding out the UV index on Android phones and tablets is still easy. Using Google search, you can find the UV index. 

What Is UV Index

The Google app has a weather section. Open Google and search for the weather. The information for your location will be presented to you. Scroll down to find the UV index.

4. Weather Channel And Weather Apps

The results you see on Apple’s weather app and Google search are usually gotten from the weather channel. You can use the weather channel app to get the UV index.

There are other dedicated weather apps you can find on the Play Store that will do a good job of telling you your UV index wherever you are.

5. Receive EPA Alerts

The EPA is a good source for all information related to the weather and environment. You can sign up to receive all kinds of updates from them.

Note that this is available only for people in the U.S, but for other countries, they have similar government bodies. Also, note that you may not receive updates during government shutdowns.

To signup to receive UV updates from the EPA, follow these steps:

Go to the Enviroflash UV index forecast page

Type your email in the “Email address” box

What Is UV Index? How To Check UV Index

Choose when to receive alerts. For instance, you can choose to be alerted only when the UV Index is high (6 and above)

What Is UV Index? How To Check UV Index
Enter your zip code or state, so you can get more accurate results for your area

Click subscribe

6. Use Dedicated UV Apps

Though weather apps do a good job of telling you what the UV index is, there are dedicated UV apps that take it to the next level. Dedicated UV apps can send notifications to you. You can also receive information fine-tuned to your skin type.

One app I would recommend is UVLens. After you have inspired your location, you will see an easy-to-read dial showing the UV index for your current location. You can turn the dial to see the Index at other times of the day.

What Is UV Index 2

Tap the “My Skin” tab to get tailored information for your skin type. You will be asked your skin color, hair color, and eye color and with that information, the app will tell you how long you can stay under the sun before you receive a sunburn.

Tap the sunscreen bottle to see how long you will last before receiving sunburns if you have applied sunscreen. You can also get reminders on when to reapply sunscreen.

You may like to read our guide on the 11 Best Skin Care Apps To Take Care of Your Skin.

How To Protect Yourself From Harmful UV Radiation

The question of what is UV index is should be clear to you by now, and you probably know how to check it. It is also important that you know how to protect yourself from harmful radiation. Here are some suggestions to protect yourself from harmful UV rays.

Limit Outdoor Stay When UV Index Is High

After you’ve checked the UV index, and then you find out it is high, stay indoors. If you must go outside, stay only for a short time to avoid sunburns. 

Wear Protective Clothing

If you will be outdoors for a long time when the UV index is high, wear protective clothes that limit the areas the sun rays directly touch. These clothes include long sleeve shirts, hats to shield your face and head, and even umbrellas. This protection can also include UV polarized sunglasses.

Use Broad Spectrum Sunscreen

Use sunscreen if you’ll be exposed to sunlight for a long time. Be sure it is a broad-spectrum sunscreen. Broad-spectrum sunscreen protects you from both UVA and UVB.

Be Careful With Reflective Surfaces

Some surfaces reflect radiation better than others. This means if you are in such environments the UV radiation would be higher than what the UV index suggests due to reflected rays.

An example of such a surface is sand. So be extra careful when you go to the beach. Another surface that reflects radiation—and this might come as a surprise —is snow. When It snows you’ll be exposed to more UV radiation than usual.

Below mentioned “How to know if your glasses have UV protection or not” is really worth watching.

How to know if your glasses have UV protection or not
Final Thoughts

In this article, I have talked about what is UV index is. The importance of the index has become apparent. Protecting one’s skin against harmful UV radiation is important.

There are several apps that not only tell you what the UV index is, but also give you meaningful pointers that will help you protect your skin. I also give other suggestions that will help you avoid harmful UV radiation.