The environment plays a large part in the impact that a sign will have in Australia. Some important questions need to be asked when determining the longevity of a sign in Australia.

• Does the Northern Hemisphere have the same climate as the Southern Hemisphere?

• Will signage last as long in Australia as they do in England and Europe?

• What other environmental issues may affect the life of a sign?

The longevity of a sign in Australia is affected by many factors. These include:

• The amount of sun exposure

• The temperature where the sign will be located

• The surface colour of the sign

• The environment where the sign will be installed

• The chemical composition of the films

• The thickness of the ink coating

• The amount of UV radiation that the sign will have

Although each of these factors influence how long your sign will last and so the effectiveness of the message, there is little doubt that the most significant factor in sign longevity is UV radiation.

Although it is self evident that the Northern Hemisphere and the Southern Hemisphere have two very different climates very little thought is given to the affect on signs placed in different areas of the world. Signs that are used in countries such as Australia, New Zealand and other countries below the equator are impacted the most as they have the highest levels of UV intensity.

The reasons for this are based on science and our knowledge of how the atmosphere is changing over time. The ozone layer, or our atmosphere, absorbs UV rays from the sun. The amount of UV radiation that reaches the ground is controlled by two factors – the amount of ozone (typically 90% in the stratosphere) and the amount of cloud cover. Data shows that increased UV radiation under clear skies is caused by decreases in the stratospheric ozone. That is the less ozone and cloud cover the more damage caused.

Another factor affecting the Southern Hemisphere is the hole in the ozone layer. The hole in the ozone layer has developed over the last 50 years, and is caused by the introduction of harsh chemicals which breakdown the ozone through photochemical processes. These chemicals include choro-fluoro-carbons (CFCs), bromo-fluoro-carbons (halons) and methyl bromide.

One problem is that in most parts of the world there is little damage caused due to a slow chemical reaction. However, due to the unusual atmospheric conditions that exist during winter in the Southern Hemisphere, every spring a dramatic hole opens above Antarctica. As a result, high levels of UV rays are able to pass through.

All signage material manufacturers use a worldwide standard rating system to determine the life of material based on application being 90 degrees vertical and facing north. However, one of the most important pieces of advice in positioning your sign is to get it absolutely right. If you tilt the sign backwards by as little as 5 degrees and you will reduce the life of the sign by 50 percent.

Whilst UV light is the most important, other factors that affect the life of the sign, which may be just as damaging, are dirt, salt, acid rain, general pollution and more. All of these factors can reduce the life span of your signage, and need to be taken in to consideration.

To ensure that you have a sign that is cost-effective, conveys your message clearly and lasts, then you need to pay attention to detail across every aspect of development.

• Choose the right material for your sign, based on the conditions that it will be placed in.

• Make sure that your sign substrate or vinyl is free of any contaminants by washing with a mild detergent first and when dried wiping with a solvent saturated cloth.

• Position your sign to reduce the affect that the environment will have on it.