22.47 Worded road markings placed transversely across the carriageway (see table 22-3) are elongated in the longitudinal direction, keeping the transverse dimension unchanged. This makes it easier for a driver to read the legend. Those not so placed are listed in table 22-4; these are not elongated.
22.48 Figure 22-10 shows how elongation is achieved, using the letter "A" as an example. The base character is taken from the Transport Medium alphabet at an x-height of 400 mm and therefore a capital letter height of 560 mm (see Chapter 7, para 2.8). The letter is drawn on a grid measuring 70 x 70 mm (i.e. 560 / 8). The 1600 mm size character is elongated in the ratio of 200 / 70 and the 2800 mm size in the ratio of 350 / 70.
22.49 To set out an elongated worded marking on the carriageway, the following method is suggested:
(i) determine how much of the carriageway width is available for the word, allowing a minimum of 300 mm clear at either side,
(ii) decide on the size of the alphabet required from the appropriate section of this chapter,
(iii) add up the tile widths from table 22-2 to determine the overall width of the marking,
(iv) if this width is less than that calculated at (i) above, then the word may be positioned centrally within the width available,
(v) if the width is more than that calculated at (i) above, then a suitable abbreviation will need to be considered where permitted, e.g. for lane destinations. Prescribed markings such as SLOW must not be abbreviated.
22.50 Diagrams 1058 (END) and 1058.1 (SLOW) are for use on cycle facilities and are therefore reduced in size. The width of the marking (excluding the outside edge of the first and last tiles) is prescribed in the Regulations. These markings do not follow the standard rules for elongation outlined above.
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