Sharing the road with trucks and buses: No Zones, passing and stopping
Where truck blind spots are, why trucks need more room and how to pass safely
Picture yourself in the middle lane at 65 mph, with your exit half a mile ahead and a tractor trailer filling the right lane beside you. Do you speed up and slip in front of it, or ease off and tuck in behind it?
In 2024, 5,340 people died in crashes involving large trucks. Of those who died, 7 in 10 were riding in other vehicles [1]. The National Highway Traffic Safety Administration (NHTSA) estimates that the toll fell about 7% in 2025, to 4,982 [5]. That is still more than 13 deaths every day (our calculation).
Here’s the physics behind what commercial vehicle safety specialists teach, plus a No Zone table and passing checklist for your next highway trip.
Why truck crashes are so lopsided
NHTSA defines a large truck as one with a gross vehicle weight rating above 10,000 pounds. In 2024, they were 5% of registered vehicles and 10% of vehicle miles traveled, but 9% of vehicles in fatal crashes [1].
Weight explains why most of the harm lands on the smaller vehicle. The Federal Motor Carrier Safety Administration (FMCSA) notes that a loaded tractor trailer can weigh up to 80,000 pounds [3]. Trucks are often 20 to 30 times as heavy as passenger vehicles [3]. Compared with a 4,000 pound car, that rig is 20 times heavier. In a collision, the car’s speed therefore changes about 20 times as much as the truck’s (our calculation).
The Insurance Institute for Highway Safety (IIHS) documents the human cost. In 2024, 96% of occupants killed in two vehicle crashes between a passenger vehicle and a large truck were in the passenger vehicle [2]. IIHS and NHTSA percentages differ slightly because the agencies classify motorcyclists differently [1, 2].
Buses are involved in far fewer fatal crashes. FMCSA’s latest Large Truck and Bus Crash Facts counts 213 buses in fatal crashes in 2022, compared with 5,837 large trucks [4]. Most were school buses (87) or transit buses (74) [4]. Still, buses share the big blind spots, wide turns and long stopping distances that make trucks risky to crowd [3].
Why tractor trailers need more distance to stop
IIHS says loaded tractor trailers need 20% to 40% more stopping distance than cars. The gap widens on wet roads or with poorly maintained brakes [2]. FMCSA says a large truck or bus can need up to two football fields to stop safely [3]. That is about 600 feet, or more than 6 seconds of travel at 65 mph (our calculation).
Two more factors add distance:
- Brake lag: Tractor trailers use air brakes [8]. Unlike a car’s hydraulic brakes, which respond almost instantly, air brakes need half a second or more to engage, adding about 32 feet at 55 mph [6].
- Hot brakes: Brakes weaken as they heat up, which happens on long downhills. New York’s manual shows a tractor trailer at 55 mph needing about 256 feet to stop with cool brakes, but 430 feet with hot brakes [8].
Comparison compiled by Safety Behind the Wheel Foundation
| Source and speed | Passenger car | Large truck | What the figure includes |
|---|---|---|---|
| New York driver manual, 55 mph [8] | 193 feet | 256 feet (cool brakes); 430 feet (hot brakes); 249 feet (empty) | Braking tests plus a reaction distance |
| California commercial driver handbook, 55 mph [6] | Not given | More than 450 feet | Spotting the hazard, reacting, brake lag and braking, in good conditions |
| Pennsylvania driver manual, 65 mph [9] | 400 feet | At least 600 feet (loaded) | Good tires and brakes on a clear, dry road |
The figures differ because sources assume different reaction times, brakes and road conditions. The pattern holds, though: at the same speed, a truck needs more room than you do.
The No Zones: where truck and bus drivers can't see you
Truck drivers sit high and use large mirrors. Yet they still have big areas they can’t see, which safety programs call No Zones. FMCSA’s rule of thumb is simple: if you can’t see the driver’s face in their mirror, the driver can’t see you [3].
Comparison compiled by Safety Behind the Wheel Foundation
| Zone | Why the driver can’t see you | What to do |
|---|---|---|
| Front | The long hood hides a low car. The blind area can reach 20 feet ahead of the cab [8, 10]. | Pull in front only when the whole front of the truck shows in your rearview mirror. |
| Left (driver’s) side | Side blind spots are much larger than a car’s [8]. | Pass steadily. Don’t cruise beside the cab or trailer. |
| Right (passenger) side | Usually the largest side zone. The driver sits on the left, and commercial driver manuals note that drivers can’t see as well toward the right [7]. | Don’t pass on the right. Stay clear when the truck may turn or merge right. |
| Rear | The trailer blocks the view straight back. The blind area can stretch about 200 feet [10]. | Drop back until you can see both side mirrors. |
If a truck drifts toward you while you’re in a No Zone, stay calm and decide quickly whether to speed up or slow down [9].
Wide turns and the right turn squeeze
A long vehicle’s rear wheels track inside its front wheels. So the driver must swing wide to keep the trailer off the curb [9]. Large vehicles may need more than one lane to start or finish a turn [11]. That is why a truck or bus turning right often moves left first [3, 8].
That opening on its right looks inviting. But a truck driver has no view of a car that slips in beside the curb, Pennsylvania’s manual warns [9].
- Trust the turn signal, not the lane position: A truck drifting left with its right signal on is setting up a right turn.
- Never pass on the right of a turning truck or bus: Stay behind it until the turn is complete [10].
- Stop behind the stop line, because a truck turning into your street may need part of your lane.
- Never cut behind a truck that is backing up: Wait until it’s done [8, 9].
Following a truck or bus: stay back and stay visible
Following closely puts you in the rear No Zone and hides the road ahead. Pennsylvania’s manual says you need at least 4 seconds to stay out of a truck’s rear blind spot [9]. At 55 mph, that is about 320 feet (our calculation), well beyond the 200 foot rear blind area Virginia describes [10].
Space also protects you in sudden stops. In 2024, the truck was hit in the rear in 22% of two vehicle fatal crashes between a large truck and another vehicle [1].
- Leave room when stopped: A truck may roll back slightly as it starts, especially uphill, so stop several car lengths behind it [3, 11].
- Dim your high beams: Your headlights reflect off a truck’s large mirrors and can blind the driver [9].
- Back off in rain: Spray from big tires can blind you. A longer gap leaves time to steer around debris such as shredded tire treads.
Our safe following distance guide shows how to count seconds.
How to pass a truck or bus safely
Tractor trailers can stretch 65 feet. On a two lane road, Virginia’s manual says you may need over half a mile of open road to get past one [10]. On a highway, a pass can take up to 30 seconds [9]. Traveling 5 mph faster than the truck, you gain only about 7 feet per second (our calculation).
When a truck passes you, move toward the far side of your lane and ease off the gas slightly [9]. On two lane roads, keep as far right as is safe when meeting a truck, to reduce wind turbulence [9]. New York’s manual cautions that an approaching big rig may be moving faster than it looks [8]. Our guides to lane changes and blind spots and highway merging cover the basics.
Never cut in front: the most dangerous move
The open space ahead of a truck is its safety cushion. Pennsylvania’s manual points out that a driver who cuts in and then brakes leaves the trucker almost no time or space to respond [9].
By Pennsylvania’s figures, a loaded truck needs at least 600 feet to stop from 65 mph. A car needs 400 feet [9]. That is 200 extra feet, about 2 seconds of travel or 13 car lengths (our calculation). If you pull in 100 feet ahead and brake, the truck has about 1 second of space, far too little to stop a loaded tractor trailer.
Give trucks room to merge, too. FMCSA asks drivers to leave extra space so trucks and buses can change lanes safely. It also asks them to be patient while they build speed [3].
Underride: stay out of the gap beneath a trailer
Trucks ride high, so a smaller vehicle can slide under a trailer in a crash, which is called underride [2]. The car’s front end, designed to crush and absorb energy, may pass beneath the trailer. Then the trailer strikes the windshield area instead. A 1997 IIHS study estimated that underride happened in half of fatal crashes between large trucks and passenger vehicles [14].
Rear guards are the steel bars across the back of a trailer. A 2022 NHTSA rule requires stronger guards on trailers built since July 15, 2024 [12]. They must protect the passenger compartment in 35 mph crashes into the guard’s center or with half the car’s width overlapping [12]. The rule doesn’t cover crashes into the guard’s outer corner, older trailers or single unit trucks, such as many box and dump trucks [12]. IIHS’s TOUGHGUARD award adds a tougher corner test. In North America, 10 trailer makers now build guards that qualify [14].
Side guards aren’t required in the U.S. [14]. In 2023, NHTSA estimated that about 89 light vehicle occupants die each year in side underride crashes with trailers [13]. It projected that guards on every trailer would save about 17 lives a year. IIHS puts the potential at 160 to 220 [13, 14]. NHTSA’s estimate is lower partly because it found only about 1 in 5 of these crashes happen at speeds where guards would work [13].
Your best protection is space, whether you’re moving or stopped. At night, slow down near rural intersections and driveways, where a long trailer may be crossing your path.
Hills, wind, work zones and buses
- Hills: Trucks lose speed climbing and gain speed descending. So be patient on upgrades and never pass a truck going downhill [3, 9]. Never stop or park near a runaway truck ramp, an escape lane for trucks that are out of control or have lost their brakes [9].
- Wind and rollovers: Expect a blast of air when you pass or meet a truck [9]. Trucks must slow sharply for curves and ramps. Of truck occupants who died in 2024, 47% were in rollovers [2]. Don’t crowd a truck on a ramp.
- Work zones: Only 5% of fatal large truck crashes in 2024 happened in work zones [1]. Yet the Federal Highway Administration reports that large trucks or buses were involved in 31% of fatal work zone crashes that year [15]. Merge early and leave extra room, as our work zone guide explains.
- Breakdowns: If you break down, get as far from passing trucks’ wind and spray as you can. Our roadside breakdown guide explains how.
City buses stop often and must merge back into traffic. When a bus signals to pull out, give it room. Watch for riders crossing near the stop. For school buses, see our school bus and school zone guide.
Tips for teens, parents, and RV or trailer drivers
Teens: Say the mirror test out loud on highway drives until it becomes automatic. Practice your first truck passes on a multilane highway in light daytime traffic, with a parent along.
Parents: Ask your teen to identify each No Zone and explain choices, such as staying behind a truck before an exit. Model the same habits, because your teen is watching.
RV and trailer drivers: Virginia’s manual says pulling a trailer roughly doubles the time your vehicle needs to pass, stop, accelerate and turn [10]. You now have your own No Zones and wide turns, so leave extra following distance and use towing mirrors. Downshift before long downhills to protect your brakes. Pull over where it’s safe to let traffic pass.
Frequently asked questions
How far behind a semi truck should I drive?
Stay at least 4 seconds back, which keeps you out of the rear blind spot [9]. Add more time in rain, at night or on downgrades. Back off whenever you can’t see the truck’s side mirrors.
Which side of a truck has the biggest blind spot?
The right side is usually the largest, because the driver sits on the left and can’t see as well toward the right [7]. Avoid passing on the right, especially near a truck that is turning.
When is it safe to pull in front of a truck after passing?
Wait until the whole front of the truck, including both headlights, appears in your rearview mirror [9, 11]. Then maintain your speed so the truck keeps its stopping distance.
Do I have to let a bus pull out from a stop?
In some states, yes: Oregon, for example, requires drivers to yield to a transit bus reentering traffic when its yield sign flashes [11]. Elsewhere, yielding is still the safer choice.
What is a runaway truck ramp?
It’s an escape lane on a long downgrade for trucks that are out of control or have lost their brakes [9]. Never stop or park near one.
The bottom line
Recommendation from Safety Behind the Wheel Foundation
Assume every truck and bus can’t see you in its No Zones and can’t stop as quickly as you can. Pass on the left without lingering. Move back only when the whole front of the truck appears in your mirror. Otherwise, stay well back. Never cut in front or squeeze in on the right of a turning truck.
Related articles
- Safe following distance: the 3 second rule and when to add more
- Lane changes and blind spots: a safe routine every driver can use
- Merging and highway driving: how to enter, cruise and exit safely
- Work zone and move over safety: protect road crews, responders and you
- Roadside breakdown safety: what to do when your car breaks down
Sources and further reading
- 1National Highway Traffic Safety Administration (NHTSA). Large Trucks: 2024 Data. Traffic Safety Facts, DOT HS 813 816. June 2026. crashstats.nhtsa.dot.gov/…/813816
- 2Insurance Institute for Highway Safety (IIHS). Fatality Facts 2024: Large Trucks. Posted June 2026. iihs.org/…/large-trucks
- 3Federal Motor Carrier Safety Administration (FMCSA). Our Roads, Our Safety: Tips for Passenger Vehicle Drivers. Updated September 29, 2026. fmcsa.dot.gov/ourroads/…
- 4FMCSA. Large Truck and Bus Crash Facts 2022. FMCSA-RRA-24-001. Released October 2025. fmcsa.dot.gov/…/large-truck-and-bus-crash-facts-2022-1
- 5NHTSA. Early Estimates of Motor Vehicle Traffic Fatalities and Fatality Rate by Sub-Categories in 2025. DOT HS 813 829. July 2026. crashstats.nhtsa.dot.gov/…/813829
- 6California Department of Motor Vehicles. California Commercial Driver Handbook, Section 5: Air Brakes. Accessed October 3, 2026. dmv.ca.gov/…/section-5-air-brakes
- 7New Jersey Motor Vehicle Commission. Commercial Driver License Manual (PDF). Version March 2025. nj.gov/mvc/…/CDL_Manual.pdf
- 8New York State Department of Motor Vehicles. Driver’s Manual, Chapter 11: Sharing the Road. Accessed October 3, 2026. dmv.ny.gov/…/chapter-11-sharing-the-road
- 9Pennsylvania Department of Transportation. Pennsylvania Driver’s Manual: Special Circumstances and Emergencies (sharing the road with trucks and buses). Accessed October 3, 2026. pa.gov/…/special-circumstances-and-emergencies
- 10Virginia Department of Motor Vehicles. Virginia Driver’s Manual (DMV 39D, PDF). Accessed October 3, 2026. dmv.virginia.gov/…/dmv39d.pdf
- 11Oregon Department of Transportation, Driver and Motor Vehicle Services. Oregon Driver Manual, Section 4: Sharing the Road. Accessed October 3, 2026. oregon.gov/…/Study-Section_4.aspx
- 12NHTSA. Federal Motor Vehicle Safety Standards; Rear Impact Guards, Rear Impact Protection. Final rule, Federal Register 2022-14330. July 15, 2022. federalregister.gov/…/2022-14330
- 13NHTSA. Side Underride Guards. Advance notice of proposed rulemaking, Federal Register 2023-08451. April 21, 2023. federalregister.gov/…/2023-08451
- 14IIHS. Large Trucks (research area: underride guards and crash avoidance). Updated September 2026. iihs.org/research-areas/large-trucks
- 15Federal Highway Administration (FHWA). 2026 National Work Zone Awareness Week Factsheet. FHWA-HOP-26-060. April 2026. ops.fhwa.dot.gov/…/HOP-26-060
This article reflects the safety priorities of commercial vehicle operations and crash prevention around large trucks and buses. It is general education, not legal or professional advice for any individual. Figures marked as our calculations are simplified examples. Laws, data and vehicle features change, so verify details with official sources. Reviewed October 2026.
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