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UV Radiation: UVA, UVB and the UV Index

11:00
10 July 2022

Safety in the sun
UV Radiation: UVA, UVB and the UV Index

sunshine

As temperatures are rising across the British Isles, most of us are spending more time outside. But with the longer, hotter and sunnier days comes the danger of increased ultraviolet (UV) radiation.

UV radiation is a type of energy produced by the sun ray's and is the main cause of skin cancer.

The sun's UV rays can reach people in three ways: directly from the sun, scattered and/or reflected by the environment depending on the time of day, season and your location.

Even on a cloudy day, UV levels can be high as it is able to be reflected and scattered in the clouds.

There are three types of UV rays: UVA, UVB and UVC. UVC is the most dangerous form of UV radiation, but luckily this is absorbed by the atmosphere before it reaches Earth. UVB penetrates the top layer of the skin and leads to sunburn.

UVA, however is the most potent source of UV which we are exposed to all year long. UVA can even pass through windows and clouds and penetrates deep into our skin leading to ageing and increases our risk of skin cancer.

Because of the dangers associated with increased levels of UV, particularly in the summer months when UV radiation is at its strongest, the UV Index was created:

The UV Index helps individuals make decisions about how much time should be spent in the sun and what level of protection will be needed.

The higher the UV Index, the stronger the strength of the UV and faster skin will burn.

Across parts of the UK, UV levels are forecast to reach 7 or 8 on the UV Index.

When UV levels are forecast this high, it means there is a risk of burning within 15-30 minutes, with individuals advised to keep out of direct sunlight around midday.

It is also important to make sure protective clothing is worn and sun scream with an SPF of 30 is applied every two hours to prevent sunburn and irritation.

Weather & Radar editorial team
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