Missouri CDL — General Knowledge: Traffic Laws Practice Test

Question 1

If your commercial license is revoked, suspended, or canceled, how quickly must you notify your employer?

Accepted Answer

Within two business days — A driver whose license is suspended, revoked, canceled, or who is disqualified must let the employer know within two business days.

Answer

Within thirty days

Answer

Within one week

Answer

Only if the employer asks

Question 2

Within how long after a conviction for a traffic violation must you tell your employer about it?

Accepted Answer

Within 30 days — You are required to inform your employer within 30 days whenever you are convicted of a traffic offense other than parking, no matter what vehicle you were driving.

Answer

Within 24 hours

Answer

Within 90 days

Answer

Only at your next annual review

Question 3

What does the federal regulation say about reading or sending text messages while operating a CMV?

Accepted Answer

It is completely prohibited while driving — Manually entering or reading text on an electronic device while driving a commercial vehicle is prohibited.

Answer

It is allowed at stoplights

Answer

It is allowed for work-related messages

Answer

It is allowed if you use voice-to-text

Question 4

When applying for a commercial driving job, how many years of past driving employment must you disclose?

Accepted Answer

The past ten years — You must give a prospective employer a record of every driving job you have held over the previous ten years.

Answer

The past three years

Answer

The past five years

Answer

Only your current job

Question 5

At what blood alcohol concentration does the law make it illegal to operate a commercial motor vehicle?

Accepted Answer

At 0.04 percent or more — Operating a CMV with a blood alcohol level of .04 percent or above is against the law for a commercial driver.

Answer

At 0.10 percent or more

Answer

At 0.08 percent or more

Answer

There is no legal limit for commercial drivers

Question 6

After the initial cargo check, how often must a driver re-inspect the load and its securing devices?

Accepted Answer

Every 150 miles or 3 hours, and after each break — Following the first check, you must look at the cargo again after driving three hours or 150 miles, whichever comes first, and after each break.

Answer

Every 500 miles only

Answer

Once per day of driving

Answer

Only when the load looks loose

Question 7

When must a commercial driver wear a safety belt?

Accepted Answer

At all times while operating the vehicle — The rules require you to be properly buckled by a safety belt the entire time you are operating a commercial vehicle.

Answer

Only on the highway

Answer

Only when a passenger is aboard

Answer

Only during inspections

Question 8

If you have any measurable amount of alcohol below .04 percent in your system, what happens?

Accepted Answer

You are placed out of service for 24 hours — Any detectable alcohol under the .04 threshold puts a commercial driver out of service for 24 hours.

Answer

Nothing, because you are under the limit

Answer

You lose your CDL for a full year

Answer

You receive only a written warning

Question 9

Which statement best describes the federal rule on hand-held mobile phones while driving a CMV?

Accepted Answer

Holding the phone is banned; only hands-free use with a single-button dial is allowed — A driver may not hold a phone to talk or press more than one button to dial; if you use a phone at all it must be a hands-free unit within easy reach.

Answer

Hand-held calls are fine on the interstate

Answer

You may text but not talk

Answer

Phones are permitted as long as you slow down

Question 10

Obtaining a hazardous materials endorsement requires you to submit to what, in addition to a knowledge test?

Accepted Answer

Fingerprinting and a TSA background check — A hazmat endorsement calls for fingerprinting and a background check administered through the Transportation Security Administration.

Answer

A road test in a tank truck

Answer

A hearing exam

Answer

A ten-year employment audit

Question 11

By operating a commercial vehicle, a driver is treated as having agreed to what?

Accepted Answer

Alcohol testing — Driving a CMV means you are deemed to have consented to testing for alcohol.

Answer

A yearly vision exam

Answer

Random cargo weigh-ins

Answer

Waiving the right to a hearing

Question 12

How many driver licenses may a commercial driver legally hold?

Accepted Answer

Just one — The rules allow you only a single license, and breaking that rule can bring a court fine or jail time.

Answer

Two, one for personal and one for commercial use

Answer

As many as the number of states you drive in

Answer

Up to three at a time

Traffic Laws

Study questions with answers

1. If your commercial license is revoked, suspended, or canceled, how quickly must you notify your employer?

2. Within how long after a conviction for a traffic violation must you tell your employer about it?

3. What does the federal regulation say about reading or sending text messages while operating a CMV?

4. When applying for a commercial driving job, how many years of past driving employment must you disclose?

5. At what blood alcohol concentration does the law make it illegal to operate a commercial motor vehicle?

6. After the initial cargo check, how often must a driver re-inspect the load and its securing devices?

7. When must a commercial driver wear a safety belt?

8. If you have any measurable amount of alcohol below .04 percent in your system, what happens?

9. Which statement best describes the federal rule on hand-held mobile phones while driving a CMV?

10. Obtaining a hazardous materials endorsement requires you to submit to what, in addition to a knowledge test?

11. By operating a commercial vehicle, a driver is treated as having agreed to what?

12. How many driver licenses may a commercial driver legally hold?

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