Table 2. Mean velocity of an automobile according to the type and width of roads (km/h).

		Width (m)
	Type	≥13	5.5–13	3–5.5	<3	Unknown
Urban	Highway
	(Inter-city)	80	80	50	10	2
	(Intra-city)	60	60	50	10	2
	Main road
	(National)	30	20	17	7	2
	(Prefectural and municipal)	30	17	17	7	2
	Other road and unknown	30	12	8	4	2
Rural 1	Highway
	(Inter-city)	80	80	60	15	10
	(Intra-city)	60	60	60	15	10
	Main road
	(National)	50	40	25	10	10
	(Prefectural and municipal)	50	35	25	10	10
	Other road and unknown	50	20	15	10	10
Rural 2	Highway
	(Inter-city)	80	80	60	15	10
	(Intra-city)	60	60	60	15	10
	Main road
	(National)	55	50	30	10	10
	(Prefectural and municipal)	55	45	30	10	10
	Other road and unknown	55	30	15	10	10

Road density: Urban, ≥15,000 m/km²; Rural 1, 5,000~15,000 m/km²; Rural 2, <5,000 m/km².