Handling Emergencies

Study questions with answers

7 sample Handling Emergencies questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. Which statement best describes what antilock brakes actually do for you?

   Correct answer: They keep the wheels from locking during hard braking so you stay in control, though they may not shorten stopping distance

   ABS is an add-on to your normal brakes that activates only when the wheels are about to lock; it helps you hold control during hard braking but does not necessarily shorten how far it takes to stop.

   Source: Michigan CDL Manual — Section 5.1.16: Antilock Braking Systems (ABS)

2. 2. Suppose the low-pressure warning activates while you are driving. What is the safest thing to do?

   Correct answer: Stop and safely park as soon as possible, because there may be an air leak

   Treat the warning as a possible leak: stop and park while there is still enough air to use the foot brakes, since controlled braking is only possible while air remains in the tanks.

   Source: Michigan CDL Manual — Section 5.4.7: Low Air Pressure

3. 3. On a tractor or straight truck, the spring brakes will come fully on once air pressure drops into which range?

   Correct answer: 20 to 45 psi (often 20 to 30 psi)

   As tank pressure falls into roughly the 20-to-45 psi band, most often 20 to 30 psi, the springs come fully on; you should not wait for that to happen while driving.

   Source: Michigan CDL Manual — Section 5.1.14: Spring Brakes

4. 4. Which sequence correctly describes stab braking?

   Correct answer: Press the brakes fully, release when the wheels lock, then reapply fully once the wheels roll again

   Stab braking means full application, releasing the moment the wheels lock, then reapplying fully after the wheels start rolling; it can take up to a second for them to roll again.

   Source: Michigan CDL Manual — Section 5.4.3: Emergency Stops

5. 5. Why can a heavily loaded vehicle take a long distance to stop once the spring brakes apply on their own?

   Correct answer: Spring brakes do not act on all axles, so a heavy load has less braking to stop it

   Because the spring brakes act on only some axles, a heavily loaded truck needs a long distance to stop; that is another reason to stop while you still have foot-brake air.

   Source: Michigan CDL Manual — Section 5.4.7: Low Air Pressure

6. 6. When the low air pressure warning first lights up and buzzes while you are driving, what should you do?

   Correct answer: Stop the vehicle safely without delay, while you still have enough air to control the brakes

   Rather than waiting for the spring brakes to grab on their own, stop safely as soon as the warning appears, while there is still enough air to control the brakes.

   Source: Michigan CDL Manual — Section 5.1.14: Spring Brakes

7. 7. What describes the "controlled braking" method for an emergency stop?

   Correct answer: Braking as hard as possible without locking the wheels, keeping steering movements small

   In controlled braking you apply firm pressure just short of locking the wheels and keep steering inputs small; if the wheels lock or you must steer more, release and then reapply as soon as you can.

   Source: Michigan CDL Manual — Section 5.4.3: Emergency Stops