Dermatology - Sun Protection

This leaflet has been given to you because we suspect you may have a daylight allergy. People with daylight allergies need to take extra care in the sun. This leaflet contains tips to help.

Summary

Protect your skin from ultraviolet by:

●    Staying out of the sun when it’s strongest (11am-3pm)
●    Wearing a broad brimmed hat
●    Covering your skin with tightly woven fabric
●    Fitting UV window film to windows
●    Wearing sun cream with SPF50 and UVA 4 or 5 star rating
●    Additional measures are also available to protect skin against visible light, if this is the problem.

Why does the skin need protection from sunlight?

It is important to protect our skin from too much sunlight. Too much can cause skin cancer and is the main cause of skin aging. Sunlight can also cause rashes in some patients with daylight allergies.

What is daylight?

The sun gives us 3 things:

Heat - this does not cause daylight allergies

Invisible light or ultraviolet (UV) - this is the most common cause of daylight allergies. It is invisible to human eyes so we can’t see it!

Visible light - this allows us to see and is why it goes dark when the sun sets

Whenever there is daylight there is some ultraviolet…. it's just a question of how much. There is less ultraviolet in winter - more in summer. There is less ultraviolet on a cloudy day - more on a clear day…. but it’s always there!

How can I protect myself from daylight?

There are 3 main ways to protect yourself:

1.    Spending less time in the sun
2.    Physical barriers
3.    Sunscreens

Spending less time in the sun

The sun is strongest between 11am and 3pm. During this time, you should seek natural shade. It isn’t practical to avoid the sun all the time, so if you do have to go out during those times seek natural shade. The shade should be deep shade!

●    Light bounces from different surfaces
●    Water can dazzle in the sun because so much light is reflected
●    Up to 80% of light reflects from snow
●    Light also reflects from sand and concrete

Imagine you are sitting under a parasol. The parasol protects you from the light above, but the light can bounce up and hit you in directions you weren’t expecting. The solution is to be in the deep shade.
 

Physical barriers to sunlight

Hats

Hats are very good at protecting your head and face. A hat should have a broad brim and not be made of straw. Dark colours are best!

A baseball cap only protects the top of your head and your nose! Ears, cheeks, neck will all still catch the sun.

The way you wear the hat is also important, as shown in this picture.
 

 UV umbrellas

Many manufacturers now make UV umbrellas. They can look like a standard umbrella and are available in a range of designs.
Search for UV umbrellas on the internet.

Sunglasses

Sunglasses should be 100% UV protection (look for the CE mark and BS-EN 170 2002 or sunglasses marked UV400). Buy your sunglasses from a reputable shop and avoid fakes that may not give enough protection.

The style should be large or wrap around. Opticians provide UV coatings on regular glasses that are clear.

If you don’t like wearing dark sunglasses in the winter, discuss with your optician about the possibility of “clear sunglasses”.

Clothing

Clothes can be effective in stopping the light reaching your skin. Try to choose:

●    Long sleeves and trousers
●    Shoes or trainers rather than sandals
●    Shirt collars provide protection for the neck
●    Silk scarf or Buff™ can help protect the neck
●    Consider gloves made for runners/cyclists
●    Loose fitting clothing is better

Choosing the right material

Don’t assume all clothes are effective in protecting you from the light. Many things can affect how much light will pass through fabric.

3 most important are:

●    Weave
●    Material
●    Colour

Weave

The structure of the weave (knitted, woven etc.) and the weight (how heavy and how many fibres were used) will affect how much light passes through fabric.

Hold it up to the light and look at the weave. Does it look like it lets a lot of light through? Trust your rash. If the rash comes up under your clothes then the light has come through. Keep a diary about what you wear. If your rash appears the day after sun exposure you can look back to what you were wearing.

Material type

Good choices include polyester, silk, tightly woven cotton.

Colour

Fabric should preferably be dark not white. Many people think it’s the other way round! Dark colours are best. Other factors can also have an effect:

●    Wet (e.g. sweaty) fabric lets through more light
●    Stretched fabric will let through more light
●    The SPF of cotton goes up the first time it is washed

What about windows in the car or at home?

Windows block ultraviolet B (UVB) but let ultraviolet A (UVA) straight through.

In cars the windscreen is laminated by law, so it doesn’t let any ultraviolet (UV) light through. However, the side windows on most cars will let UVA through.

UVA light will also flood into a conservatory. UV light will also come through house and workplace windows.

How to block UV light coming through windows

UV window film is a clear film that blocks UV light. It does not change colour and is different from tinted windows. UV window film is effective for sun allergies to UVA.

Where can I get the film from?

If you have access to the internet, you can search for UV blocking window film.

Alternatively, you could try contacting the: European Window Film Association EWFA Regional Office Avenue Jules Bordet 142, B - 1140 Brussels, Belgium www.ewfa.org

Also, inexpensive products are now available on amazon.co.uk.

Once you have bought the UV window film you can apply it yourself or alternatively you can take your car to a garage that does window tinting and ask them to put the film on for you.

Don't forget

UV window film is not the same as tinted windows. Tinted windows may not protect you from UV light.

Technical details

In general UV protective window films block all UV from
300-390nm. They only let through approximately 1% of UV light between 390 and 400nm. Between 400 and 410nm they let through 46% and between 410 and 420nm they let through 63.5%.

For more information have a look at the European Window Film Association website: www.ewfa.org.

Those with sensitivity to visible or infrared light may have to consider additional coverings for windows in their houses and car.

What about room lights (light bulbs)

Some light bulbs can give out ultraviolet light and if you are VERY sensitive this can be a problem.

●    Avoid fluorescent strip light bulbs unless they are fitted with a plastic diffuser
●    Compact fluorescent bulbs should be the double envelope type
●    LED bulbs are the best

What about sunscreens?

Sunscreens are available on prescription for patients with sun allergies. We can currently prescribe either Uvistat or Anthelios sunscreen.

The sun protection factor (SPF) tells you how much the sunscreen protects you against ultraviolet B.

 

The star rating, UVA circle or PA system tells you how much the sunscreen protects you against ultraviolet A.

The star rating ranges from one star (minimum protection) to five stars (maximum protection)

 

The UVA circle indicates that the UVA protection is at least a third of the SPF of the sunscreen

 

The PA system, ranges from PA + (minimum protection) to PA +
+++ (maximum protection)
 

Look for SPF50 or above with a star rating of 4 or 5 (or a PA +++ or PA ++++).

Sunscreens can go off in the heat so avoid storing them in direct sun, hot cars etc. Sunscreens usually last for 12-18 months once open.

You should apply sunscreen generously; around 2 teaspoonfuls if you’re just covering head arms and neck, and around 7 teaspoonfuls for the whole face and body. Apply smoothly and evenly. Don’t rub in.

Apply a double coat before going out and reapply frequently (at least every 2 hours).

If you are using a moisturiser or steroid cream, make sure that is applied before your sunscreen - wait 20-30 minutes before applying your sunscreen.

Treat “waterproof” and “once a day” claims with caution. Sprays, “oils” and roll-ons can result in you applying less.

Most people don’t apply enough sunscreen.

What happens if the doctor has said my problem is visible light?

Some people are allergic to visible light, for example patients with conditions such as erythropoietic protoporphyria (EPP) or solar urticaria (SU).

Visible light is different from ultraviolet light. Some things that work for ultraviolet light will also work for visible light.

For example:

●    Stay out of the sun when it’s at its strongest
●    Protect your skin with clothing
●    Wear a hat and sunglasses.

If you have a problem with visible light the doctor will recommend specific sunscreens.

What is Dundee cream?

Dundee cream was originally invented at a hospital in Dundee. It comes in 3 colours: beige, coffee or coral. It is specially made to block visible light. Dundee cream is usually only available from a hospital pharmacy and is difficult to obtain at present.

Are there any alternatives to Dundee cream?

Dundee cream is the only visible light blocking sun cream available on prescription. However, there are now some newer sunscreens advertised as being able to block visible light in addition to UV.

We don’t know exactly how effective all of them are but if you wanted to try it, we would recommend just using it on a small area of skin first to see if it works for you. An example of a broad spectrum sunscreen with visible light protection is Anthelios “The Mineral One” which is available in a range of colours.

Window film

UV window film is not very good at blocking visible light. To block visible light, you will need to use a special yellow window film.

You are not allowed to put this film on car windows because you must have clear vision in a car! The yellow window film is called Amber Madico.

Contact us

If you need any further advice we will do our best to help. Photobiology Unit - 0161 206 4081 (9am to 3pm)
Email: Photobiology.Salford@nca.nhs.uk