UV protection Films

Window films provide increased protection to eyes and skin from UV rays and the harmful effects of the sun.

Subject to the type of film, this technology can block up to 99% of both UVA rays and UVB rays (those that cause sunburn) all year long.

Protecting property against fading

The sun can destroy the colour of pictures, photos, curtains, clothes and furniture. It can also cause damage to paint, wood and other materials be it at home or in your shop display window.

UV is Not the Only Cause of Damage

Fading is usually thought to be caused by Ultra Violet light in sunlight. In fact, fading is caused by all parts of the solar energy reaching the earth: UV, Visible Light and solar heat all cause fading and damage. Approximately 90% of fading and damage is from solar energy.

Who can benefit by protecting goods and materials from fade and damage?

Museums can protect their paintings and other works of art, artefacts, clothing, etc. from damage caused by solar energy – and can provide a good optical environment for conservation work without distortion of colours.

Businesses can protect their investments in furniture and office equipment as well as carpets, curtains, etc.

Shop and home owners can reduce damage to valuable goods and merchandise.

How much slower will materials fade with UV protection film?

As a guide, window films double the time taken for the same amount of fade / damage. However, it is essential to remember that different materials react in very different ways. The types of materials, fabrics, dyes and colours used to manufacture your product strongly influence the extent of fading and damage resulting from solar energy; natural fibres (such as silk) and natural colours tend to fade and be damaged quicker than synthetic materials. And fading is no respecter of the cost or value of the goods – some expensive products can fade remarkably quickly.

Key points

• Fading cannot be stopped although in the majority of cases it can be reduced

• UV is the most important part of solar energy to filter, but filtering visible light and/or infra-red energy may also be needed

• Delicate or valuable items require more protection from sunlight than others

It is essential to ensure the best choice of window film is selected. Specification of window films for fade reduction is relatively easy and advice is available from manufacturers, distributors and authorised dealers.

How to Specify the Correct Film

The selected film must offer protection from fading and damage over a number of years. Good durability UV reducing films show only a small increase in UV transmission after the equivalent of several years’ exposure to sunlight, compared to the high UV transmission of other films.

Conservation of Valuable Items: Museums, Art Galleries, etc.

UV

They require the UV to be reduced to very low levels. A special measure of the quantity of UV in visible light is used, called microwatts per lumen (or μW/lumen). It is usually required for the UV to be < 75 μW/lumen and even < 10 μW/lumen. Many window films will provide < 75 μW/lumen; specialist films will reduce UV to < 10 μW/lumen or even < 5 μW/lumen.

Visible Light

The amount of visible light allowed in the museum depends upon the sensitivity of objects to visible light.

A Scottish Museum gives recommendations for maximum light levels:

• 50 lux for sensitive items
• 200 lux for moderately sensitive items
• 300 lux for insensitive items

These recommendations mean that some areas may need little reduction in the amount of visible light transmitted by the glazing while other areas need a very high reduction in visible light transmission.

The 50 lux value may require visible light transmission to be reduced to much less than 5%.

Infra-red energy

The requirement for filtering Infra-Red (IR) energy also depends upon the type of object being protected. Objects that are subject to thermal stress damage or to drying out (which then causes damage) will obviously require better protection than non-IR sensitive items.

Specification for UV, Visible and IR

All three aspects, UV, Visible Light and IR, need to be considered according to the objects being protected. A simple method of selecting the appropriate film is to choose between specifying a clear film or a solar control film.

Offices and Other Workplaces

Many offices suffer from solar gain and glare related problems. By using solar control window films, you can resolve these issues and reduce UV and infra-red transmissions that can cause damage to property and health.

Shops and Homes

Many shops and homes require maximum light transmissions through their glass; a slight tint is acceptable, but often no more.

It is essential to reduce UV light to very low levels while reducing a little of the visible light and direct infra-red energy transmission can provide extra protection.