to be told that they may pass either side of an obstruction. We recommend that the signs at figures 135 to 138 and 97 be used for this purpose and set at an appropriate distance in advance of the particular hazard. It will also be necessary at times to warn pedestrians against traffic approaching from an unexpected direction; in such cases the sign at figure 139 should be used.
196. An obstruction by road works is not less dangerous because it is of short duration or because it is moved forward as the work progresses. These are not sufficient reasons for putting up fewer signs.
197. Authorities responsible for road works should ensure in advance that their contractors are fully aware of the requirements of the Code and should also make it a condition of their contract that the correct signs in relation to the speed value of the road are properly erected and afterwards removed. Penalties for breach of this condition should be enforced.
198. Where alternate one-way working is necessary past an obstruction on a single-carriageway road, traffic should be controlled by one of the following methods:—
(a) traffic signals at extended obstructions or at small obstructions during times when traffic is dense;
(b) manually-operated Stop and Go signs, mounted back to back on a portable post, at small obstructions of short duration provided traffic is not dense; or
(c) the signs shown at figures 23 and 132 to indicate which direction of traffic flow has priority, at places where the more rigid control imposed by (a) or (b) is not justified (see paragraph 82).
We thus recommend that red and green flags should cease to be used. The sign at figure 140 should be set at an appropriate distance in advance of the obstruction when traffic control is by method (a) or (b) above.
199. In many cases the first temporary signing of an accident or other emergency will probably be carried out by the Police using Stop police or Police slow signs (figures 142 and 143) or by motoring organisation patrols. In any case the first object should be to give as quickly as possible and well in advance of the obstruction a general warning of danger together with a command to reduce speed . Next, or preferably simultaneously, the obstruction itself must be very clearly marked. As soon as possible thereafter, and particularly if clearance of the obstruction is likely to take some time, standard signs as for road works should be used except that the Other danger sign (figure 69) should replace the Road works sign (figure 134).
200. In some Continental countries the difficult problem of quickly providing warning of an emergency is met by allowing drivers to place warning devices on the carriageway. In Italy, for example, certain vehicles are required to carry a triangular warning sign which can be placed on the carriageway not less than 50 metres in advance of an obstruction . We think that signs of this sort may be of help in reducing the risk of accidents at the scene of an emergency, particularly on motorways and other high speed roads . We understand that
the Departments are considering the introduction of Regulations permitting
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