Before entering fog check your mirrors then slow down. If the word ‘Fog’ is shown on a roadside signal but the road is clear, be prepared for a bank of fog or drifting patchy fog ahead. Even if it seems to be clearing, you can suddenly find yourself in thick fog.
Section:
Driving in adverse weather conditions (rules 226 to 237)
Subsection: Fog (rules 234 to 236)
Subsection: Fog (rules 234 to 236)