How to Work Out What Size Traffic Mirror You Need

In our latest bite-size 90 second insight video we provide answers to help people determine the right size traffic safety mirror. Read on to learn more.

Convex road safety and traffic mirrors have become increasingly ubiquitous as more people recognise the safety benefits of these simple safety mirrors. But determining the right size and type of traffic mirror can sometimes be a little confusing. When considering the installation of a traffic mirror here is what you need to know.

What is a Traffic Safety Mirror?

Traffic safety mirrors are also commonly called traffic mirrors, road safety mirrors or simply driveway mirrors. You commonly see them mounted on roadsides, opposite driveways or entrances, at tricky road junctions and in car parks. They are lightweight, robust convex mirrors, specifically designed for outdoor use in high-traffic environments.

How Traffic Mirrors Work

Convex traffic mirrors provide wide-angle reflections. This means the convex mirror surface reflects a wide view of what’s on the road, enabling drivers to anticipate hazards and avoid collisions. The wide-angle view is better than the reflection that might be provided from a plain, flat mirror as it can encompass the entire width of a road or driveway. Pedestrians or cyclists, who might be travelling close to the edge of the road, can be seen more easily, as well as larger road traffic.

The placement and articulation of a traffic mirror, along with its size, are important considerations for optimal safety performance.

Traffic Mirror Questions You Need to Consider

When considering the size and style of traffic mirror required, these are the important questions to answer:

• What is the purpose of the traffic safety mirror?
• Where will the mirror be located?
• From what distance and position will the mirror be viewed?

Traffic safety mirrors are often mounted on roadsides, directly opposite tricky driveways or entrances. This means they need to be mounted at an appropriate height from which they can be clearly seen by drivers exiting onto the roadway. The reflected mirror image needs to encompass the entire width of the road, often in two directions. This can require the installation of two convex traffic safety mirrors. Traffic mirrors, situated in locations like these, also benefit travellers on the road who can see if there is a vehicle about to join the road from a hidden entrance.

Traffic mirrors are also increasingly used in busy car parking areas, such supermarket car parks. Mirrors are typically located at car park junctions, enabling drivers to see other vehicles from multiple directions and avoid collisions. These mirrors are generally viewed from close distances.

And many people benefit from installing convex traffic safety mirrors in their driveways or at their garage entrances, helping them negotiate tight corners and narrow spaces.

What is Maximum Viewing Distance?

When considering the installation of a traffic safety mirror the optimum mirror size is an important question to consider. A convex mirror that is too small, for example, would not provide adequately useful reflections whereas an appropriately sized mirror will encompass the entire roadway and enable reliable assessment of oncoming traffic speed.

Convex road safety mirrors, of various sizes, each have a maximum viewing distance. This is the maximum distance between the viewer and the mirror that will provide reliable, safe reflections. For example, a circular convex traffic safety mirror with a diameter of 300mm has a maximum viewing distance of 3 metres. While it is entirely possible to view reflections from distances beyond this range it would not be easy to assess road traffic speed in a mirror of this size. A circular convex traffic mirror with larger diameter of 600mm has a maximum viewing distance of 11 metres and a larger, 800mm diameter mirror provides a maximum viewing distance of up to 20 metres.

Outdoor Traffic Safety Mirror Designs

If you take a look at the range of high quality traffic safety mirrors in our store you can see a variety of designs. These include mirrors with bold, striped, high-visibility frames, round mirrors, half round mirrors and rectangular mirrors.

High visibility traffic mirror frames enable these mirrors to be seen in situations where they might otherwise be obscured, such as roadside hedges. The brightly coloured frames draw attention to the mirrors and help drivers of farm vehicles and commercial trucks avoid colliding with them.

Half round road safety traffic mirrors are particularly useful in confined spaces such as multi-storey car parks, where they can be mounted against ceilings to provide car park users with enhanced visibility.

Rectangular traffic mirrors offer the same maximum viewing distance as circular mirrors of the same diameter. So a rectangular mirror that’s 600 x 400mm, mounted sideways, has the same maximum viewing distance as a circular mirror with a 600mm diameter, but doesn’t take up as much space.

Traffic Safety Mirror Materials

An important attribute of traffic safety mirrors is robustness. High quality outdoor mirrors, made from various plastics and stainless steel, are able to withstand the rigours of roadside installation without breakage. Thermoplastic mirror frames are anti-UV treated and tested to ensure they are crack resistant and don’t yellow with age. And tough, scratch resistant mirror surfaces ensure long-term mirror reliability.

Stainless steel traffic mirrors are the strongest available. These are commonly used in situations where there is risk of inadvertent collisions.

Traffic safety mirror quality and price is largely influenced by the materials from which they are manufactured. Low quality convex traffic safety mirrors, for example, tend to have very thin plastic mirror surfaces that are more susceptible to damage and indentation.

Fog Free Anti Frost Traffic Mirrors

One of the problems that can affect mirrors in outdoor applications is frost and condensation. Condensation and dew is formed on a mirror surface when air temperature rapidly changes. Moisture droplets on the mirror surface, which can freeze in low temperatures, render the mirror unusable. But there are some cleverly designed anti-frost and anti-condensation traffic mirrors that use Latent Heat Technology to avoid this problem. They don’t need an electrical supply as they effectively store thermal energy in the mirror material that is then released to prevent misting and condensation on the mirror surface.

For more information on How to Work Out What Size Traffic Mirror You Need talk to Insight Security