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JohnnyMo wrote: ↑Tue Nov 23, 2021 10:51
This 30 zone last to the end of the picket fence (just past the approaching car)
And if you look at where the car is you will that before that there is a 40 zone. Such stacked zones are quite common in rural areas. The idea is to gradually slow vehicles approaching a built up area rather than have a sudden transition from NSL to 30 or in the case you show to 20.
Most evidence suggests they don't work though.
Definitely. As long as the clear visibility to the terminals is provided a 30mph drop is perfectly OK and compliance is no worse - specially mentioned in TSM Chapter 8 U2.10.11. NSL to 30mph on a APD2 is fine in most cases but if to close to junctions etc there may be issues with excessive braking.
The shortest recommended speed limit in TSM (but unenforceable) is a 30mph limit for a substandard crossover. Depending on the number of lanes it starts somewhere about 195m long.