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2.7 Managing Space

To be a safe driver, you need space all around your vehicle. When things go wrong, space gives you time to think and to take action. To have space available when something goes wrong, you need to manage space. While this is true for all drivers, it is very important for large vehicles. They take up more space and require more space for stopping and turning.

Space Ahead

Of all the space around your vehicle, it is the area ahead of the vehicle - the space you are driving into - that is most important. You need space ahead in case you must suddenly stop. According to accident reports, the vehicle that trucks and buses most often run into is the one in front of them. The most frequent cause is following too closely. Remember, if the vehicle ahead of you is smaller than yours, it can probably stop faster than you can. You may crash if you are following too closely.

One good rule for how much space you should keep in front of you is at least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety. For example, if you are driving a 40-foot vehicle, you should leave 4 seconds between you and the vehicle ahead. In a 60-foot rig, you will need 6 seconds. Over 40 mph, you would need 5 seconds for a 40-foot vehicle and 7 seconds for a 60-foot vehicle.

To know how much space you have, wait until the vehicle ahead passes a shadow on the road, a pavement marking, or some other clear landmark. Then count off the seconds like this: “one thousand-and-one, one thousand-and-two” and so on, until you reach the same spot. Compare your count with the rule of 1 second for every 10 feet of length. If you are driving a 40 foot truck and only counted up to 2 seconds, you are too close. Drop back a little and count again until you have 4 seconds of following distance (or 5 seconds, if you are going over 40 mph). After a little practice, you will know how far back you should be. Remember to add 1 second for speeds above 40 mph. Also remember that when the road is slippery, you need much more space to stop.

Test Your Knowledge

  • How far ahead does the manual say you should look?
  • What are two main things to look for ahead?
  • What is the most important way to see the sides and rear?
  • What does “communicating” mean in safe driving?
  • Where should your reflectors be placed when stopped on a divided highway
  • What three things add up to stopping distance?
  • If you go twice as fast, will your stopping distance increase by two or four times?
  • Empty trucks have the best braking. True or False?
  • What is hydroplaning?
  • What is “black ice?”

Study sections 2.4, 2.5, and 2.6 if you can't answer all of these questions.

Space Behind

Heavy vehicles are often tailgated when they cannot keep up with the speed of traffic. This often happens when you are going uphill. If a heavy load is slowing you down, stay in the right lane if you can. Going uphill, you should not pass another slow vehicle unless you can get around quickly and safely.

In a large vehicle, it is often difficult to see whether a vehicle is close behind you. You may be tailgated:

  • When you are traveling slowly. Drivers trapped behind slow vehicles often follow closely.
  • In bad weather. Many car drivers follow large vehicles closely during bad weather, especially when it is hard to see the road ahead.

If you are being tailgated, do the following to reduce the chances of an accident:

  • Avoid quick changes. If you have to slow down or turn, signal early and reduce speed very gradually.
  • Increase your following distance. Opening up room in front of you will help you avoid having to make sudden speed or direction changes. It also makes it easier for the tailgater to get around you.
  • Do not speed up. It is safer to be tailgated at a low speed than a high speed.
  • Avoid tricks. Do not turn on your taillights or flash your brake lights. Follow the suggestions above.

Space to the Sides

Commercial vehicles are often wide and take up most of a lane. Safe drivers will manage what little space they have by keeping their vehicle centered in the lane and avoiding driving alongside others.

  • Staying centered in a lane - Keep your vehicle centered in the lane to maintain safe clearance on either side. If your vehicle is wide, you have little room to spare.
  • Strong winds - Strong winds can make it difficult to stay in your lane. The problem is usually worse for lighter vehicles. This problem can be especially bad coming out of tunnels. Do not drive alongside others if you can avoid it.
  • Traveling next to others - There are two dangers in traveling alongside other vehicles. Another driver may change lanes suddenly and turn into you. You may be trapped when you need to change lanes. Find an open spot where you are not near other traffic. When traffic is heavy, it may be hard to find an open spot. If you must travel near other vehicles, try to keep as much space as possible between you and them. Also, drop back or pull forward so you are sure the other driver can see you.

This is another very important section to understand. It is asked quite a bit on the written exam. You need to understand the full concept, but here are the main points:

  • Maintain at least 1 second for each 10 feet of vehicle length at speeds below 40 mph.
  • For speeds above 40mph add 1 additional second.
While you don't need to memorize the below list word for word, you should understand the overall concepts. A question about how to handle tailgaters may come up on the written exam.

Dm:

Dispatcher, Fleet Manager, Driver Manager

The primary person a driver communicates with at his/her company. A dispatcher can play many roles, depending on the company's structure. Dispatchers may assign freight, file requests for home time, relay messages between the driver and management, inform customer service of any delays, change appointment times, and report information to the load planners.

TWIC:

Transportation Worker Identification Credential

Truck drivers who regularly pick up from or deliver to the shipping ports will often be required to carry a TWIC card.

Your TWIC is a tamper-resistant biometric card which acts as both your identification in secure areas, as well as an indicator of you having passed the necessary security clearance. TWIC cards are valid for five years. The issuance of TWIC cards is overseen by the Transportation Security Administration and the Department of Homeland Security.

OWI:

Operating While Intoxicated

Review Questions - Click On The Picture To Begin...

If you are being tailgated, you should do the following to reduce the chances of an accident:
  • Speed up to increase the distance between yourself and the vehicle behind you
  • Flash your brake lights to communicate you want the vehicle behind you to open their following distance
  • Make a quick lane change
  • None of these answers are correct

Quote From The CDL Manual:

If you are being tailgated, do the following to reduce the chances of an accident: Avoid quick changes. If you have to slow down or turn, signal early and reduce speed very gradually. Increase your following distance. Opening up room in front of you will help you avoid having to make sudden speed or direction changes. It also makes it easier for the tailgater to get around you. Do not speed up. It is safer to be tailgated at a low speed than a high speed. Avoid tricks. Do not turn on your taillights or flash your brake lights. Follow the suggestions above.

Next
What is the proper following distance for a 40 foot vehicle traveling at 35mph?
  • 3 seconds
  • 4 seconds
  • 5 seconds
  • 6 seconds

Quote From The CDL Manual:

One good rule for how much space you should keep in front of you is at least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety. For example, if you are driving a 40-foot vehicle, you should leave 4 seconds between you and the vehicle ahead. In a 60-foot rig, you will need 6 seconds. Over 40 mph, you would need 5 seconds for a 40-foot vehicle and 7 seconds for a 60-foot vehicle.

TruckingTruth's Advice:

These types of questions almost always show up during the written exam. Be 100% confident you understand the following distance formula.

Remember: For every 10ft of you vehicles length, you need 1 second of following distance. Anything over 40mph, add 1 second to your total.

It is very important that you understand this and can calculate proper following distance for any vehicle length and any speed.

Prev
Next
When a vehicle behind you is driving too close, you should do the following to reduce the chances of an accident except:
  • Pull over to the side of the road and stop
  • Very gradually reduce your speed to encourage the vehicle behind you to pass
  • Increase your following distance to avoid making sudden speed or direction changes
  • Signal early, be extra cautious, and reduce speed very gradually

Quote From The CDL Manual:

If you are being tailgated, do the following to reduce the chances of an accident: Avoid quick changes. If you have to slow down or turn, signal early and reduce speed very gradually. Increase your following distance. Opening up room in front of you will help you avoid having to make sudden speed or direction changes. It also makes it easier for the tailgater to get around you. Do not speed up. It is safer to be tailgated at a low speed than a high speed. Avoid tricks. Do not turn on your taillights or flash your brake lights. Follow the suggestions above

Prev
Next
How much space should you keep in front of you while driving?
  • At least 2 seconds for each 10 feet of vehicle length at speeds below 50 mph. At speeds above 50, add an additional 2 seconds
  • At least 2 seconds for each 10 feet of vehicle length at speeds below 40mph. At speeds above 40, add an additional 3 seconds
  • At least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At speeds above 40, add an additional 1 second
  • At least 1 second for each 20 feet of vehicle length at speeds below 40mph. At speeds above 40, add an additional 1 second

Quote From The CDL Manual:

One good rule for how much space you should keep in front of you is at least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety. For example, if you are driving a 40-foot vehicle, you should leave 4 seconds between you and the vehicle ahead. In a 60-foot rig, you will need 6 seconds. Over 40 mph, you would need 5 seconds for a 40-foot vehicle and 7 seconds for a 60-foot vehicle.

TruckingTruth's Advice:

Knowing how to calculate proper following distance is very important and will likely show up on your written exam. Please go over this section thoroughly in your CDL manual and be sure you fully understand how to calculate safe following distance.

Prev
Next
If you are driving a 30-foot vehicle at 55 mph, how many seconds of following distance should you allow?
  • 3.5 seconds
  • 6.5 seconds
  • 4 seconds
  • 5 seconds

Quote From The CDL Manual:

One good rule for how much space you should keep in front of you is at least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety.

TruckingTruth's Advice:

A question regarding safe following distance will very likely show up on your written exam. Be sure to understand the safe driving distance formula.

Prev
Next
If you are in a 60-foot vehicle traveling 55mph, what should your following distance be?
  • 7 seconds
  • 9 seconds
  • 8 seconds
  • 6 seconds

Quote From The CDL Manual:

One good rule for how much space you should keep in front of you is at least 1 second for each 10 feet of vehicle length at speeds below 40 mph. At greater speeds, you must add 1 second for safety. For example, if you are driving a 40-foot vehicle, you should leave 4 seconds between you and the vehicle ahead. In a 60-foot rig, you will need 6 seconds. Over 40 mph, you would need 5 seconds for a 40-foot vehicle and 7 seconds for a 60-foot vehicle.

TruckingTruth's Advice:

These types of questions are very common during the written exam and can be a bit confusing as they change the size of the vehicle as well as their speeds. But it's rather simple to calculate: For each 10 feet of vehicle, you need 1 second of following distance. Anything over 40mph, simply add 1 second to your total. Be 100% confident about this formula before taking the written exam as this will probably show up.

Prev
Next
What is the most important space around your vehicle?
  • The rear of your vehicle
  • The sides of your vehicle
  • All spaces around your vehicle are equally as important
  • The area ahead of your vehicle

Quote From The CDL Manual:

Of all the space around your vehicle, it is the area ahead of the vehicle—the space you are driving into—that is most important. You need space ahead in case you must suddenly stop. According to accident reports, the vehicle that trucks and buses most often run into is the one in front of them. The most frequent cause is following too closely. Remember, if the vehicle ahead of you is smaller than yours, it can probably stop faster than you can. You may crash if you are following too closely.

Prev
Next
To determine your safe following distance, you should do all of the following except:
  • Wait until the rear of the vehicle ahead passes a shadow on the road, a pavement marking, or some other clear landmark, then count off the seconds until the front of your vehicle crosses the same fixed location
  • Check the following distance of vehicles around you and match what they are doing to keep uniformity in the driving pattern
  • If you're too close, drop back a little and recount until you have at least 1 second of spacing for every 10 feet of vehicle length (add 1 second if driving over 40mph)
  • Compare your following distance count with the rule of 1 second for every 10 feet of length

Quote From The CDL Manual:

To know how much space you have, wait until the vehicle ahead passes a shadow on the road, a pavement marking, or some other clear landmark. Then count off the seconds like this: "one thousand-and-one, one thousand-and-two" and so on, until you reach the same spot.

Compare your count with the rule of 1 second for every 10 feet of length. If you are driving a 40-foot truck and only counted up to 2 seconds, you are too close. Drop back a little and count again until you have 4 seconds of following distance (or 5 seconds, if you are going over 40 mph).

After a little practice, you will know how far back you should be. Remember to add 1 second for speeds above 40 mph. Also remember that when the road is slippery, you need much more space to stop.

TruckingTruth's Advice:

Make sure you memorize the following distance formula of 1 second of following distance for every 10ft of vehicle length (adding 1 second for speeds exceeding 40mph).

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