A4.3.20 Sign face condition: Legibility can be affected by scratches and other damage to the sign face. This can be best assessed at the appropriate viewing distance. The severity, extent and location of such damage shall be taken into account when deciding whether a sign should be classified as “unacceptable”. For example a relatively small area of damage could render a letter illegible and seriously compromise drivers’ ability to comprehend a sign. See paragraph A4.3.27 for illustrated examples.
A4.3.21 Sign face colour: If colour fading is noticeable it should be visually compared with a square of new/ perfect material. For regulatory signs such as speed limit signs, any significant colour fading may compromise regulatory enforcement, and is therefore unacceptable. For information signs, legibility and vivid colour contrasts should be the main criteria.
A4.3.22 Level of retroreflectivity: Delineators should be highly conspicuous and all signs, symbols and letters should be clearly visible during darkness. The retroreflective properties of signs and delineators can be assessed, whilst they are suitably illuminated, by visual comparison with a new/perfect sample of retroreflective material. Alternatively, the retroreflectivity properties of signs and delineators can be assessed using a field retroreflectometer and readings can be directly compared with the relevant Standard. However, the use of a retroreflectometer should normally only be required in special situations or where the results of other methods are disputed.
A4.3.23 Retroreflectivity can be significantly reduced by dew formation on the sign face, and assessments should not take place in such circumstances.
WARNING LIGHTS
A4.3.24 All lamps shall be in good working order and in good condition.
TRAFFIC SIGNAL EQUIPMENT
A4.3.25 Faulty equipment shall not be placed on a public highway. All traffic signal equipment should be inspected and tested before delivery to the site. Useful advice is contained in "An introduction to the use of vehicle actuated portable traffic lights" (Department for Transport, 2008).
TEMPORARY ROAD MARKINGS
A4.3.26 All temporary road markings such as studs, paint and tape shall be installed in accordance with the manufacturer’s instructions, and their performance regularly monitored throughout the project.
202
