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Ontario Class A (AZ) overview

Ontario Class A (AZ): Night, weather and emergencies

Headlight use, fog and whiteouts, skids and ABS, warning devices for a disabled truck, fire classes and causes, collision reporting, drowsiness and distraction.

  • 22 questions
  • Topic drill
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Night, weather and emergencies · Question 1Score 0/0

Your rig breaks down at night in a 90 km/h zone and cannot leave the road. Where do you set warning devices?

Study reference: MTO Truck Handbook (online edition, 2026), Ch. 3 Safe and responsible driving — Night and bad weather, emergencies

All 22 questions in this test

Every question and its answer choices. The correct answers and explanations appear when you take the test above.

  1. Your rig breaks down at night in a 90 km/h zone and cannot leave the road. Where do you set warning devices?

    1. About 5 m behind only
    2. On the cab roof
    3. About 30 m ahead and behind
    4. About 100 m behind only

  2. Which road surfaces freeze first as temperatures drop?

    1. Sunny, open stretches of highway
    2. Freshly paved city streets
    3. Gravel shoulders beside the road
    4. Bridges, overpasses, shade

  3. What does overdriving your headlights mean?

    1. Your high beams are much too bright
    2. Stopping distance exceeds sight distance
    3. You use your headlights in daytime
    4. Your headlights are aimed too low

  4. Which device may a commercial driver legally use while driving?

    1. A two-way radio, mic mounted
    2. A hand-held cell phone on speaker
    3. A hand-held GPS unit held at the wheel
    4. A tablet showing a movie on the dash

  5. For how long must the required warning lamps or flares be able to burn?

    1. At least 8 hours
    2. At least 1 hour
    3. At least 4 hours
    4. At least 24 hours

  6. A tire is burning on your trailer. What class of fire is that?

    1. Class D
    2. Class C
    3. Class A
    4. Class B

  7. Within what distance of an oncoming vehicle must you switch to low beams?

    1. 500 m
    2. 300 m
    3. 150 m
    4. 60 m

  8. Your truck begins to skid. What should you do?

    1. Accelerate and turn the wheel sharply
    2. Brake hard and hold the wheel straight
    3. Shift up into a higher gear right away
    4. Ease off; steer where you want to go

  9. A hill hides your disabled truck within 150 m. What should you add?

    1. An extra warning device
    2. A note on the windshield
    3. A second set of flashers
    4. Nothing more is needed

  10. What should you NOT expect from anti-lock brakes?

    1. Steering control in a hard stop
    2. Less wheel lock-up
    3. Pulsing in the brake pedal
    4. A shorter stopping distance

  11. From how far are a snow plow's flashing blue lights visible?

    1. 50 m
    2. 1 km
    3. 150 m
    4. 300 m

  12. At a collision with a fuel leak, what should you do?

    1. Move all vehicles quickly
    2. Turn off engines and keep flames away
    3. Light flares beside the leak
    4. Start the engines to clear fumes

  13. Which class of fire involves grease, oil or gasoline?

    1. Class A
    2. Class B
    3. Class C
    4. Class D

  14. A moose is standing on the road ahead. What should you do?

    1. Slow down and sound the horn
    2. Swerve around it at speed
    3. Flash your lights and accelerate
    4. Stop and get out to move it

  15. You must report a collision to police when property damage is over what amount?

    1. $1,000
    2. $5,000
    3. $10,000
    4. $2,000

  16. Which time is a peak period for drowsy-driving collisions?

    1. 8 a.m. to 10 a.m.
    2. 6 p.m. to 8 p.m.
    3. 2 a.m. to 6 a.m.
    4. 11 a.m. to 1 p.m.

  17. Several plows are staggered across a freeway clearing all lanes. What should you do?

    1. Pass between them carefully
    2. Pass on the right shoulder
    3. Flash lights so they move over
    4. Stay behind; never pass between

  18. Fog becomes too thick to continue. What should you do?

    1. Pull fully off the road and use flashers
    2. Stop in your lane with flashers on
    3. Follow the tail lights ahead closely
    4. Speed up to get out of it quickly

  19. How often should you check hub temperatures to catch overheating brakes?

    1. Only after a fire
    2. Only at inspection stations
    3. Once a week
    4. Every time you check tires

  20. Which headlights should you use in fog?

    1. No lights
    2. Parking lights only
    3. Low beams
    4. High beams

  21. A fire starts in your combination. Which step is recommended if possible?

    1. Open the trailer doors
    2. Drive to the next exit
    3. Uncouple the units
    4. Pour water on fuel

  22. Warning lamps carried on a commercial vehicle must be visible from at least how far?

    1. 150 m
    2. 500 m
    3. 30 m
    4. 60 m

Night, weather and emergencies: key rules to remember

Our summary of what the official handbook says on this topic, in our own words. Read it before or after the practice questions above, then check the original chapter. Read the official chapter ↗

Emergency warning devices

  • From one-half hour before sunset to one-half hour after sunrise, every commercial vehicle on a provincial highway must carry warning devices: flares, lamps or lanterns giving two lights each visible from 150 m for at least 8 hours, or portable reflectors.
  • If the vehicle breaks down, move it off the road if you can and turn on the hazard flashers; use low beams when visibility is limited.
  • Where the limit is over 60 km/h and you cannot get off the road, set a warning device about 30 m (100 ft) ahead of and behind the vehicle during limited visibility.
  • Limited visibility means one-half hour before sunset to one-half hour after sunrise, or any time you cannot clearly see people or vehicles 150 m away.
  • Do not leave a vehicle on the road unless moving it is impractical or there is a clear view of it for 125 m in both directions; if a hill or curve hides it within 150 m, place an extra warning.
  • Using warning devices in every breakdown, day or night, is recommended.

Fire

  • Class A fires: wood, paper, textiles, tires. Class B: grease, oil, gasoline, solvents, paint. Class C: live electrical equipment. Class D: burning metals, which need special compounds.
  • Common truck fire causes: a soft tire, overheated brakes, fuel leaks, uneven loads rubbing tires, careless smoking, carelessly placed flares, and electrical short circuits.
  • Check hub temperatures every time you check tires.
  • If a fire starts: stop away from buildings and vehicles, uncouple a combination if possible, call the fire department and say what is burning, remove battery cables if a short circuit is suspected, and keep people back if the cargo could explode.

Collisions

  • Report a collision to police when anyone is injured or damage exceeds $5,000; below that you must still exchange information.
  • With fuel leaks, turn engines off, do not move the vehicles, keep flames and flares away and warn approaching drivers.
  • Unless there is fire danger, leave injured people where they are until medical help arrives; cover them to reduce shock.

Driving at night and in bad weather

  • Overdriving your headlights means your stopping distance is longer than the distance you can see.
  • Dim your high beams within 150 m of an oncoming vehicle and within 60 m when following.
  • For oncoming glare, look up, beyond and slightly to the right of the lights.
  • In fog or blowing snow use low beams (and fog lights if fitted), slow down gradually, use the right edge of the road as a guide and never stop in a driving lane.
  • Snow plows show flashing blue lights visible from 150 m and may have a wing extending 3 m to the right; never pass between staggered plows.
  • Bridges, overpasses and shaded areas freeze first; black ice looks like shiny new asphalt.
  • After driving through deep water, test the brakes (for example a firm stop at 50 km/h) to dry them.
  • In a skid, ease off the brake or accelerator, steer where you want to go and do not oversteer.
  • ABS keeps steering control by preventing wheel lock but does not shorten stopping distance; threshold braking is used without ABS.

Dealing with particular situations

  • Drowsy-driving crashes peak between 2 a.m. and 6 a.m. and between 2 p.m. and 4 p.m.; commercial drivers are a higher-risk group.
  • The only cure for drowsiness is sleep: pull into a safe, well-lit rest stop and nap.
  • Hand-held phones are banned; commercial drivers may use a two-way radio whose microphone is securely mounted within easy reach.
  • If you see an animal, slow down and sound the horn; do not swerve around it. Report a collision with a deer or moose.
  • In construction zones obey workers and signs, avoid changing lanes and watch for sudden stops.

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