Andy Fish, a technical specialist at science-based technology company 3M, discusses the need for proper sign maintenance and ways of limiting damage.
Vehicles travelled a record 324.3 billion miles on the UK’s roads last year, making it more important than ever to enable safe and swift journeys.
Traffic signs are crucial this and to supporting road users’ experience in general. In order to be effective, a traffic sign needs four things – conspicuity, legibility, comprehensibility and credibility.
Poor maintenance of signs can compromise the first three of these, making it difficult to notice, read and understand them, respectively.
At best, this can result in a driver missing their exit. At worst, it can cause fatal accidents.
As well as reducing effectiveness, poor maintenance can decrease a sign’s lifespan, making premature replacements necessary, costing businesses and taxpayers money.
For these reasons, it is vital to take steps to ensure that signs are properly maintained.
One way to achieve this is to apply a protective overlay film to the sign. Not only can this make cleaning easier, it also offers some protection. This is particularly useful in challenging locations where signs are constantly being dirtied, whether by the environment or deliberate abuse. Another way of reducing damage is to carefully consider positioning when installing the sign.
For example, signs placed higher up will be less susceptible to graffiti, or dirt being sprayed from cars’ wheels.
On the other hand, they will also return less light to the driver. Most modern cars’ headlamps create beams with sharply-defined edges. This is ideal for illuminating the road in front of drivers, but does not allow much light to ‘spill’ upwards. Because of this, any high-mounted sign will receive less light from a vehicle’s headlamps.
It is therefore imperative to consider all the effects of sign placement during installation.
Signs should last for the duration of their warranty, which is generally longer for those made using higher performance materials. For example, Diamond Grade DG3 reflective sheeting from 3M comes with a 12-year warranty. However, signs made from these materials will still require regular upkeep and cleaning.
High performance materials also have higher levels of retroreflectivity, therefore returning more light to the driver, which enables them to be more easily seen and understood.
Nowadays, traffic signs need to be brighter than ever, particularly as the average age of drivers increases. As people grow older, they require more light to read any given piece of information. So the issue of sign maintenance, design and effectiveness is only increasing in importance.
