Defensive Driving

Defensive driving means spotting trouble early and leaving yourself room to deal with it, whatever anyone else does. It works in a company car, a delivery van, a pickup, a bus or a tractor-trailer. A larger vehicle changes the numbers, not the method.

Transportation incidents are the leading cause of workplace death in the United States. The Bureau of Labor Statistics counted 1,937 such deaths in 2024, or 38 percent of all fatal work injuries. If you drive for work, the road is likely the most dangerous part of your job. Most crashes involve mistakes that good habits can prevent or make less severe.

What You Will Be Able to Do

• Use a repeatable method for scanning and deciding, such as the Smith System or SIPDE.
• Set a following distance for your vehicle and for the conditions.
• Work through intersections and rail crossings safely.
• Adjust for rain, ice, snow, night and fatigue.
• Respond to a blowout, brake failure or aggressive driver.

Two Ways to Think About the Road

The Smith System

The Smith System is a widely taught set of five habits.

1. Aim high in steering. Look well down the road, not just at the vehicle in front. A common target is about 12 to 15 seconds ahead. At highway speed that is about a quarter of a mile.
2. Get the big picture. Take in the whole scene in all directions: the road, the sides, the mirrors, brake lights several vehicles ahead, and people near the edge of the road.
3. Keep your eyes moving. Scan continuously, and do not stare at one point for more than a couple of seconds. Check your mirrors every 5 to 8 seconds so you always know what is around you.
4. Leave yourself an out. An out is a clear path you can steer into if something goes wrong. Keep space around your vehicle, and avoid being boxed in. Know right now where you would go.
5. Make sure they see you. Use your lights, signal early, tap your horn when it helps, and try to make eye contact at crossings.

SIPDE

SIPDE is another way to think about the same work.

For example, a vehicle ahead suddenly swerves. You identify it, and you predict there is something in the road you cannot see yet. You decide to slow down and check your out, and you act right away. Do not assume the swerve was a mistake.

Following Distance

Space in front is the one thing you control, and it buys you time. Pick a fixed point, such as a sign. When the vehicle ahead passes it, count "one thousand one, one thousand two". You should not reach the point before you finish your count.

Worked example: a 60-foot truck over 40 mph needs 6 + 1 = 7 seconds. Many loaded commercial vehicles land at about 6 to 8 seconds.

Increase your distance for bad conditions. A common rule for rain is to double your normal distance. Allow much more on snow and ice, and more at night, in fog, and behind motorcycles.

Stopping Distance

Total stopping distance has three parts. Commercial driver manuals give these figures for a heavy vehicle at 55 mph on dry pavement with good brakes:

Air brakes add a delay that brings the total to over 450 feet. A car stops in less distance, but perception and reaction take just as long. Speed is what hurts you. Double your speed and your braking distance goes up about four times.

Mass matters too. A fully loaded 80,000-pound tractor-trailer at 65 mph carries more than 11 million foot-pounds of energy, around 20 times what a 4,000-pound car carries at the same speed. That energy has to go somewhere.

Space and Blind Spots

Stay out of other vehicles' blind spots, because the driver cannot see you and may change lanes into your space. Pass large trucks steadily, and do not linger beside them. If you drive a truck or van, know your own blind spots, and use your mirrors and a slow, signaled lane change.

If someone tailgates you, do not speed up and do not brake-check. Ease off gently to open more space in front of you, so you can brake slowly if you must. Let them pass when it is safe.

Intersections

Roughly 40 percent or more of crashes happen at or near intersections, depending on the study. Angle (T-bone) crashes from cross traffic are the classic intersection collision.

• As you approach, ease off and cover the brake, meaning hold your foot over the pedal. Do this even on a green light.
• Look left, right, then left again before you enter. Someone may run the red.
• Watch for pedestrians and bicycles, especially when you turn.
• A green light that has been on a while is stale. Be ready for it to change.
• Right of way is something you give. If another driver will not stop, yield.

Slow down and cover the brake any time you see children near the road. A ball, a bike or a child can appear in an instant, and they rarely look first.

Reduce your speed before a curve, not in it. Brake on the straight, then accelerate gently once you can see the exit.

Railroad Crossings

Slow down and look both ways at every crossing, and do not stop on the tracks. Trains cannot swerve, and at 55 mph a freight train can need a mile or more to stop. If your vehicle stalls on the tracks and a train is coming, get out and move away at a 45-degree angle toward the direction the train is coming from, so debris does not hit you. Call the number on the blue Emergency Notification System sign at the crossing.

Driving in Rain

• Slow down. Reduce speed by about a third on wet roads.
• Hydroplaning happens when your tires ride up on a film of water. It can start at about 30 to 35 mph with enough water, and worn tires and low pressure make it worse. Roads are slickest in the first 15 minutes of rain, when oil and water mix.
• If you hydroplane, ease off the accelerator, avoid hard braking, and keep the wheel steady until you feel the road again.
• Turn on your headlights. Many states require them when your wipers are on.
• Do not drive through standing water of unknown depth. The National Weather Service says 12 inches of rushing water can carry away most cars, and 2 feet can carry away SUVs and trucks. After driving through water, press the brakes lightly to dry them.

Driving on Ice and Snow

• On packed snow, reduce your speed by half or more. On ice, go at a crawl or get off the road.
• Black ice is a clear layer that makes the road look just wet. It forms first on bridges, overpasses and shaded spots, because these cool faster. If the spray from other vehicles suddenly stops, or ice is building on your mirrors, suspect it.
• If you hit black ice, ease off the accelerator and coast through. No sudden steering, braking or acceleration.
• Brake early and gently, in a straight line. Use a lower gear on hills.
• Clear all snow and ice off your vehicle before you go.
• Where chain laws apply, know them, and practice fitting chains before you need them. Follow the chain maker's speed limit, often 25 to 30 mph.

Night Driving

With low beams you can see about 250 feet ahead, and with high beams about 350 to 500 feet. Overdriving your headlights means going so fast that your stopping distance is longer than the distance you can see. At 55 mph a heavy vehicle needs over 400 feet, so slow down at night.

If oncoming high beams blind you, look toward the right edge of the road, and slow down if you need to. Keep your windshield clean inside and out, because dirt makes glare worse. Dim your own high beams for oncoming traffic and when you follow someone.

Fatigue

Tired driving is impaired driving. Your body wants to sleep most between midnight and 6 a.m. and again in the mid-afternoon. Warning signs are heavy eyelids, yawning, drifting out of your lane, missing signs, and not remembering the last few miles.

The only cure for fatigue is sleep. Coffee, cold air and the radio can buy a few minutes, but they do not fix it. When you notice the signs, stop at a safe place and sleep. A short nap can help for a while. Most adults need 7 to 9 hours of sleep to stay alert. Plan your trip to make that possible.

Distraction

Looking away from the road for 5 seconds at 55 mph means driving the length of a football field blind. Put your phone out of reach. Most states ban texting while driving, and many ban hand-held phone use. Set your navigation before you move, and pull over to deal with anything else.

Emergencies

Tire Blowout

1. Hold the wheel firmly with both hands. A front blowout can twist it hard.
2. Stay off the brake. Braking can cause you to lose control.
3. Keep going straight and ease off the accelerator gradually.
4. Once you have slowed down, brake gently and steer to a safe spot.
5. Turn on your hazard lights.

Brake Failure

1. Downshift to the lowest gear you can, and use the engine to slow down.
2. On hydraulic brakes, pump the pedal quickly. It may build enough pressure to help. Do not pump air brakes.
3. Apply the parking brake gradually so you do not lock the wheels and skid.
4. Look for an escape: a runaway truck ramp on a grade, an uphill slope, or an open field. Make your move as soon as you know the brakes are gone.
5. Use your horn and lights to warn others.

Steering Around a Hazard

You can often steer around something faster than you can stop. Steer smoothly and firmly, and do not brake hard while you turn sharply, because that can cause a skid or a rollover. Countersteer gently to get back in your lane.

Aggressive Drivers

Do not race, block or gesture back. Let an aggressive driver pass and create space. Avoid eye contact. Move out of the passing lane when someone faster comes up behind you.

If a driver follows you, stay in your vehicle, keep your doors locked and windows up, and do not go home. Drive to a police or fire station or a busy, well-lit public place while you call 911. Give the vehicle description, plate, location and direction. If you are driving a marked company vehicle, remember that your behavior represents your employer.

If You Drive a Commercial Vehicle

Some rules apply only to commercial motor vehicles (CMVs). Your employer will tell you if yours counts.

Common Mistakes

Check Your Understanding

You are driving a van in light rain at 55 mph and start to feel the steering go light. What is happening and what do you do?

You are starting to hydroplane. Ease off the accelerator, avoid hard braking, and hold the wheel steady until the tires grip again.

A car tailgates you on a two-lane road. What is your best move?

Slowly open more space ahead of you, so that you can stop gently if needed, and let the car pass where it is safe. Do not speed up or brake-check.

You drive a 40-foot straight truck at 60 mph. How many seconds should you leave?

One second for each 10 feet gives 4 seconds, plus 1 for speed over 40 mph, so 5 seconds. Add more in poor conditions.

A pickup you do not recognize has followed you through four turns, and the driver is shouting. What do you do?

Keep your doors locked and windows up, do not go home or stop to talk, and drive to a police or fire station while you call 911.

On a clear cold morning, you cross a bridge and feel the rear of your car move. What should you do?

Suspect black ice. Ease off the accelerator and coast through with no sudden moves, then slow down for the rest of the trip.

Key Takeaways

• Keep your eyes moving, look well ahead, and always know your out.
• Leave at least 3 seconds in a car, and 1 second per 10 feet of length in a large vehicle, plus 1 second over 40 mph.
• Slow down by a third on wet roads and by half or more on packed snow.
• For a blowout, hold the wheel, stay off the brake, and slow gradually.
• Sleep is the only cure for fatigue.
• Never get drawn into a fight on the road. Create distance and call for help if you need to.