Traffic Signs Manual Chapter 4 Warning Signs
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DEVIATION OF ROUTE 3.1 Bend signs 3.1.1. Diagram 512 (S2‑2‑8, see Figure 3-1 ) may be used to give advance warning of a bend which a driver might find difficult to negotiate without slowing down and the severity of which cannot easily be seen either by day or by night. The symbol should indicate a bend to the left or right as appropriate. The degree of danger at a bend varies mainly with four factors – the speed of approach, the radius of curvature, the superelevation and the skid resistance of the road surface. No uniform objective test can be applied and traffic authorities must rely on a subjective assessment of these factors when deciding whether or not to use the sign. Care should be taken to ensure that a route is signed uniformly. 3.1.2. The radius of curvature not only affects the safe speed appropriate to the bend, it might also reduce forward visibility so that drivers need to slow down. 3.1.3. The sign should be used sparingly and only to indicate a bend hazard. It should not be used simply to allay local apprehension regarding the speed of traffic. Over-use of the sign could compromise its contribution to road safety and add to sign clutter. 3.1.4. On high standard all‑purpose dual carriageway roads, consideration should be given to erecting the signs in advance of bends of radius less than 450 metres. 3.1.5. Edge of carriageway markings may be used with this sign. It might also be appropriate to change the centre line to a warning line. Chapter 5 gives further guidance on the use of these markings. 3.1.6. Where junctions which warrant signing in accordance with 2.2.1 occur on sharp bends, use of diagrams 512.1, 512.2 or 512.3 (S2‑2‑9 to 11, see tải về 2.25 Mb. Chia sẻ với bạn bè của bạn:
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