SARTSMA is the trade body for companies that manufacture and supply road traffic signs and associated products for use in South Africa. Its members are committed to following all the relevant national standards, and have prepared this guidance document for those purchasing road traffic signs, to assist and ensure that you receive the product you need that will perform well for its intended life. The current standard relevant to the manufacture and appearance of road traffic signs in South Africa is SANS 1519-2:2004 “Performance Requirements for Road Signs”. The standard incorporates SANS 1519-1:2013 “Retro-reflective Sheeting Material”, and references different reflective sheeting performance classes, so it is not enough to simply request that a sign be made to the standard, as you may receive only the lowest class of reflective sheeting, which may not provide adequate night time performance of the sign. You will therefore need to specify the correct sheeting class that you want for the sign. A recommended guideline for selecting the appropriate reflective sheeting class is provided in the “Sign Face Sheeting” section, below. The SANS 1519-1 & 2 standards are currently under review by the SABS Technical Committee, of which SARTSMA is a member, and further guidance documents will be published on the SARTSMA website if any changes occur to these standards. For signage contracts on National and Provincial routes (i.e. those roads that are maintained by SANRAL or the Provincial Roads Authority), the sign manufacturer and /or installer should be registered with the Construction Industries Development Board (CIDB). Some local authorities may also have this requirement for their own roads. The CIDB grading structure is used to determine the minimum supplier level for a particular contract, as determined by the client. The CIDB registration certificate will state a grade level that the manufacturer or installer of the signs has been assessed to meet, based on information provided regarding the value of work that is in progress or recently completed and verified with regular tax clearance certificates from the registered sign manufacturer / installer.
Checklist for Specifying a Road Traffic Sign
The list below provides the minimum information needed and should help to avoid missing anything essential. More detail should always be given, when available, and will help the supplier to deliver exactly what you want and expect.
Checklist
Guidance on the above checklist is available from SARTSMA members and more information is provided in the sections below. If you have any other specific requirements, such as the need for documentation or test certificates, this should be requested at the time of purchase, as these may not easily be provided at a later date.
Sign Face Sheeting
Traffic sign faces are covered with durable plastic material that is usually retro-reflective. Signs intended only for pedestrians may not generally need to be reflective, as they are unlikely to be illuminated by vehicle headlamps. Retro-reflectivity is achieved either by incorporating glass beads into the material, or by moulding tiny prisms into the plastic, and are therefore known as glass bead or micro-prismatic sheeting. However, it is the retro-reflective performance, not the underlying technology, which is important to the sign specifier. Therefore, you should not specify a particular technology type or trade name for the reflective sheeting, and should simply refer to the required class of reflective sheeting. A recommended guideline, for reflective performance class, is provided below:
Sign Substrates
The SANS 1519-2 traffic sign standard provides specifications for the stiffness required for a traffic sign but does not specify what material the substrate should be made from. There may be some good reasons why you might want to choose a particular type of material for the sign substrate:
To minimise the scrap value and therefore the likelihood of theft
For reasons of economy, particularly for temporary signs
To make the sign easier to handle and mount
Coastal / other installations with high corrosion possibility
Unless you specify otherwise, a sign will usually be made of 1.4mm pre-painted galvanized steel (1mm for panelled direction signs), stiffened by galvanized steel channels or square hollow tube sections affixed to the back. This will provide excellent structural support, but you may also wish to consider:
Traffic Grade Composite Sheet
Composite material has an LDPE (polyethylene) core between aluminium skins. It provides similar structural support, but is lighter in weight.
Glass Reinforced Plastic (GRP)
GRP is a light weight substrate that is often used in areas prone to theft, and particularly for temporary signs. GRP does not offer the same structural support as other materials, so requires more supporting channels, and is generally limited to small and medium-sized signs.
Aluminum
Usually made of 3mm (11 gauge) aluminium alloy, stiffened by aluminium channels affixed to the back, it provides excellent structural support and is very resistant to corrosion. You should avoid using substrate manufacturers’ brand name for sign substrates, as suppliers should be free to use any compliant material from an approved source. The back of the sign will generally be grey in colour, but the SADC sign manual also requires you to specify white for the back of Stop Signs. The back of the road traffic sign should also be clearly marked with the sign manufacturer’s name or logo and the date of manufacture, for warranty purpose.
Poles and Supports
Poles for road traffic signs may be manufactured from 76-110mm diameter, 1,6-5mm thick mild steel, hot dipped galvanized, painted with a base primer and 2k baked or natural cure paint finish or timber poles, complying with SANS 457-3:2000. Guidelines and information on supports and foundations for road traffic signs can be found on www.nra.co.za This document is available in PDF format under “Downloads”
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