The posted limit is 55 mph, but dense fog makes it hard to see ahead. What should you do?

• A.Drive 55 mph because that is the posted limit
• B.Drive at a speed that is safe for the foggy conditions, even if well below the posted limit
• C.Turn off your headlights and follow taillights
• D.Stop in a travel lane until fog clears

Why

A posted limit is the maximum for ideal conditions, not a target. You must slow down for fog, rain, snow, traffic, or any condition that makes the posted speed unsafe.

Manual topic: Pennsylvania Driver's Manual (PUB 95) - Chapter 3: Learning to Drive · From the Pennsylvania Learner's Permit (Car) practice bank (PAC-030).

Practice the full Pennsylvania Learner's Permit (Car) test

More Speed Limits & Following Distance questions

• Unless a different limit is posted, what is the statutory speed limit in a Pennsylvania residence district?
• Unless otherwise posted, what is the statutory speed limit in a Pennsylvania urban district?
• Unless otherwise posted, what is the statutory speed limit in other Pennsylvania locations outside residence and urban districts?
• What is the speed limit in a Pennsylvania school zone when it is in effect?
• It starts to rain and the road becomes slick. How should you adjust your speed and following distance?