There are various types of reflective traffic sign materials, all offering different material design and makeup, varying levels of reflectivity, and consequently, suitability to different applications.
To differentiate between the reflectivity of each traffic sign material, classes or grades are assigned to the materials – including class R3C. These regulated classes can denote where the sign material is designed to be used, for example for signs in the countryside, or signs in bright, populated areas.
But why are traffic sign materials so important, and why should we have different classes? Aren’t the brightest reflective signs the best? Not always!
The visibility of traffic signs is called conspicuity. If signs aren’t reflective, they risk not being conspicuous during dark hours, as drivers may not see them from far away, illumination methods could fail, or any number of other reasons! Depending on the placement of the sign, the purpose, the angles of approach, the level and more, the demands for reflectivity for conspicuity can change.
N.B. R3C references are always to R3C-UK, the UK standard for R3C materials. Other countries and authorities may have their own standards concerning this class.
What are the traffic sign material classes?
Here are the classes of reflective materials for permanent traffic signs within the UK:
Engineering grade reflective materials, made with glass bead construction and providing the lowest light return of all the classes for permanent traffic signs. As it is the lowest grade, it is usually not recommended for use on UK traffic signs.
Within this class, there are high intensity glass bead materials – with a medium to low light return – and high intensity prismatic (HIP) materials that offer more light return. This class is used for pretty much all UK traffic signs unless a higher performance is required.
This class consists of materials made from improved micro prismatic materials like RA2/R2. This class gives superior light return to the above classes.
R3C class materials that are constructed using the latest full cube design, offer the most light return of all the UK classes. The improved full cube micro prismatic construction maximises reflection of light. It is specified when high performance is required, and for overhead signs.
What is class R3C reflective?
This class was created in January 2018 as part of an addition to the UK National Annex – BS EN 12899-1:2007.
Within the new annex, class R3C is used to differentiate reflective materials that are particularly high performing. Specifically, R3C materials used on overhead signs reflect more light than any other classes of material. This was identified as beneficial for HGV drivers, who have additional sign reflection needs due to the higher driver positioning.
The descriptor ‘high performance’ means strong reflection. Reflection can mean mirror or diffuse reflection, however retroreflection is most suited to traffic signs. This type best fulfils the requirements for traffic signs as retroreflection ensures any light that lands on traffic signs during dark hours is reflected back to the driver, even when entrance angel and observation angle are considered.
R3B vs R3C
Both R3B and R3C classes consist of more efficient micro prismatic technology – R3B products normally use traditional truncated prisms, whereas R3C often use a full cube construction which are proven to be more efficient.
Although both classes are very effective at returning light to the driver, R3C performs higher technically, and is therefore the highest available class.
Find out more about Avery Dennison full cube products here:
How do class R3C reflective materials work?
Class R3C materials use improved full cube micro prismatic technology to leverage material makeup and ensure the maximum amount of product surface is actively reflecting.
Due to this technology, R3C reflective materials reflect at the most extreme observation and entrance angles compared to other classes – hence why it is considered the ‘best’. This means that class R3C signs can be seen at more degrees, broader levels, and longer distances (as well as very short distances).
See more details and diagrams on page 19 onwards of the UK Design Manual for Roads and Bridges. Within this document, there is also a coefficient of retroreflection levels table (page 27).
As demonstrated above, the reflectivity of R3C at various angles is optimum for HGV drivers as the angle and light amount is unlike that of cars. However, lots of modern cars have sharp cut offs on headlights to reduce light spillage, which can also impact the amount of light that reaches higher signs. As signs may be more or less visible (or conspicuous) depending on the placement of the sign relative to the driver and the headlights, more reflective efficiency is required to ensure signs are always visible to drivers, regardless of placement, light spillage, or vehicle.
Taking all of the above into account, class R3C materials are particularly valuable when signs are in less visible areas for drivers (i.e. right mounted), angled, or high.
Where are class R3C materials used?
The class of material required for permanent signs is calculated by considering vehicle position, driver level, distance, and urgency. All these aspects – matched with the above effectiveness – make class R3C products greatly suited to a variety of uses, whether that’s long or short distances, high speed roads, urban areas or more.
According to the National Annex, class R3C materials should be used in: “Locations where high-performance materials more suitable for overhead gantry signs are required.” [page 59]. This is where the relevance to HGV drivers is made.
The annex also states class R3C materials “may be useful in other driving scenarios”. The given example for this is, in areas with high background luminance, such as shopping areas. Due to the additional surrounding light, traffic signs must be exceptionally reflective to remain conspicuous with light pollution considered.
Buy class R3C – UK grade reflective material for road traffic signs
At Lakeside Group, we supply a variety of road traffic sign reflective materials, ranging from R1 through to RA2, R3B and R3C. As the UK supplier of market leader Avery Dennison materials, we offer high quality products trusted around the world, with leading product warranties.
All of our products are CE marked, as required by law, so you can be assured of the quality and performance of the materials you have specified.
When you source traffic sign materials through us, we provide up to 15-year warranties on our products, so your signs stay conspicuous and high performing for longer. This longer warranty ensures that your signs aren’t defective overtime, especially after testing the coefficient of retroflection (which happens after 7 years from installation for class RA1 and 10 years for other classes).
If you’re looking for unrivalled durability for your permanent traffic signage, check out the below video to find out more about our winning combination of 15 year R3C micro prismatic sheeting, durable TrafficJet inks and OL-1200 dew-resistant overlay film.
To find out more about our range of products and specify the right product for your needs, get in touch with one of friendly team!
For more helpful knowledge and downloads from industry leaders in the Association for Road Traffic Safety and Management (ARTSM), check out the ARTSM downloads page.