Page:UK Traffic Signs Manual - Chapter 8 - Part 1 (Traffic Safety Measures and Signs for Road). Designs 2009.pdf/160

DUAL CARRIAGEWAY ROADS *there is not an approach bend with a superelevation larger than 2.5 %;
 * absolute change in camber less than 5 %.

If any of the information given above is not available, it is recommended that the 3 step increase lengths should be used. These figures are valid where:
 * maximum adverse crossfall less than 7 %;
 * maximum adverse camber from downhill gradient-crossfall combination less than 7 %;
 * absolute change in camber less than 10 %.

If any of the values for the 3 step increase lengths are exceeded then the site is not recommended as a suitable location for a crossover.

If the characteristics of the road do not match those covered by paragraphs D6.5.9 or D6.5.10, or if site constraints mean that a shorter crossover is required, then the advice from TA 92 should be used.

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