You are driving a car on an automobile road, and thick fog has cut visibility to about 80 metres. There is no variable speed limit sign and no other sign setting a separate speed. What maximum speed must you observe?
💡 Hint
First find the maximum speed for that type of road, then apply the reduction rate required by the weather (Article 19(1)2 and 19(2) of the Enforcement Rule). Note that a road wet from rain and fog limiting visibility to 100 meters or less call for different reduction rates.
Answer: ③
Explanation
Under Article 19(1)2 of the Enforcement Rules, the maximum speed on an automobile road is 90 km/h. Under Article 19(2)2, when fog or similar reduces visibility to 100 m or less, the maximum speed must be cut by 50%, giving 45 km/h. 72 km/h would be the value for a 20% reduction, as when the road is wet from rain.
Legal basis: 도로교통법 시행규칙 제19조 제1항 제2호·제2항 제2호