This short chapter covers the situations that call for adjusting how you drive rather than following a fixed rule: sudden animal crossings, low-visibility conditions like fog and smoke, rain and hydroplaning, and night driving.
The most-tested concepts are what NOT to do when an animal darts into the road (never swerve into oncoming traffic or off the roadway to avoid it), the headlight rules for low beams (dimming within 500 feet of an oncoming vehicle and within 300 feet of a vehicle you're following), and using headlights — not just parking lights — the moment you turn on your wipers or drive in fog, smoke, or heavy rain.
A common mistake is assuming high beams help in fog; they actually reflect back and reduce visibility further. Another is trying to drive through a flooded roadway instead of turning around — water depth and current are impossible to judge from the driver's seat.
What should I do if an animal suddenly runs into the road?⌄
Slow down, tap your brakes, and sound your horn if you have time, but never swerve into oncoming traffic or off the roadway to avoid the animal — losing control causes worse crashes than hitting it.
When must I switch to low-beam headlights at night?⌄
Within 500 feet of an oncoming vehicle and within 300 feet of a vehicle you're following, so you don't blind the other driver.
Why shouldn't I drive through a flooded road?⌄
You can't reliably judge the water's depth or current, and your vehicle could stall, float, or be swept away — always turn around and find another route.