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

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

D6.5.10 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.

D6.5.11 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.

Table 6.1 Lane 1 or 2 into offside lane

and

	Temporary mandatory speed limit
	30 mph		40 mph		50 mph
Step increase	Crossover length	Paved length (m)	Crossover length (m)	Paved length (m)	Crossover length (m)	Paved length (m)
0	108	72	135	81	153	99
3	180	108	216	135	261	153

Table 6.2 Offside lane into offside lane

and

	Temporary mandatory speed limit
	30 mph	40 mph	50 mph
Step increase	Crossover length (= paved length) (m)	Crossover length (= paved length) (m)	Crossover length (= paved length) (m)
0	90	108	126
3	153	180	216

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