to the intended direction of travel on the motorway. We feel it should not be necessary to devise a special sign to deal with the rare driver who might venture on to the motorway with insufficient fuel to take him to the next intersection, and we do not therefore consider that there is any need to add such a sign to the number of signs before each intersection which our recommendations necessarily entail.
137. The sign we recommend to be sited one mile in advance of the service area is illustrated in figure 48. It shows the distance to the service area and also, where appropriate, the distance to the next service area beyond the one the driver is now approaching.
138. The sign we recommend to be sited half a mile in advance of the service area is illustrated in figure 49. Just as the second advance direction sign for intermediate junctions (paragraph 87) adds to the information contained in the first and gives the names of places which can be reached by leaving the motorway at the junction, so this sign indicates the main facilities available at the service area. It will be seen that the individual facilities are indicated by symbols only, a petrol pump (similar to the European sign) for fuel, a knife and fork for meals, a cup for snacks and the international white on blue P for parking facilities; we believe that reliance on symbols makes for a very much livelier sign and constitutes a welcome departure from the usually unnecessary but nevertheless widespread practice of duplicating messages on traffic signs by means of both words and symbols . We are convinced that drivers will find these symbols self- explanatory. It will also be seen that no reference is made to toilets and telephones, on the principle that these can be assumed to form part of any services, and on the same principle no reference is made to the transport cafes since transport drivers will quickly learn that all service areas contain them; we feel, however, that the refuelling facilities are sufficiently important to justify departing from this principle, and that the vehicle parks should also be indicated to show that they are a separate facility in their own right and to serve as a reminder that stopping on the motorway is prohibited .
139. The sign we recommend to be sited at the beginning of the deceleration lane leading to a service area is illustrated in figure 50. It is identical with the previous sign except that the legend 'Services m' is replaced by an arrow and the word 'Services'.
140. Exit distance markers, of the kind recommended in paragraph 91 and illustrated in figure 31, should be erected in advance of the beginning of the deceleration lane.
141. The sign illustrated in figure 51 is recommended for use in the point of land between slip road and motorway, where it fulfils the same function as the supplementary exit sign for intermediate junctions recommended in paragraph 94. Where the slip road leaves the motorway at so narrow an angle that there is not room between them for this sign if it is to be read from the critical point, the sign illustrated in figure 52 should be used instead .
142. On the slip road itself a sign is necessary to mark the point where the motorway Regulations cease to apply and beyond which vehicles are therefore
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