Vertical alignment. The length of a grade should not exceed the critical length, so as to avoid vehicle speed drops of more than 15 km/hour. When the length of such a grade exceeds the critical length, additional climbing lanes are required to enable slow vehicles to travel on them without their speed decrease affecting the capacity of the road.
Appears in 4 contracts
Sources: Agreement on International Roads in the Arab Mashreq, Agreement on International Roads, Agreement on International Roads