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Driving in Fog

Fog is not named anywhere in 49 CFR 383.111(a)(12)’s extreme-conditions list (bad weather, hot weather, mountain driving), so this topic is tested under the general safe-operations knowledge area, 383.111(a)(1)(ii). One rule is directly codified regardless of that gap: 49 CFR 392.14 requires a driver to discontinue operation if conditions, including fog, become too dangerous to continue safely.

Practice Driving in Fog

5 Questions

  1. Why does the guidance for driving in fog say to slow down before entering a fog bank, rather than waiting until visibility is already reduced?
  2. Why should a driver use low-beam headlights, not high beams, when driving through fog?
  3. If fog becomes so dense that a driver cannot see far enough ahead to drive safely, what should the driver do?
  4. Why shouldn't a driver in fog assume that a set of taillights visible ahead marks the safe location of the road?
  5. Why should a driver avoid passing other vehicles while driving in fog?