SGI SGI Air Brakes Endorsement

Question 1

What is the minimum air pressure required before a driver can move an air brake-equipped vehicle?

Accepted Answer

100 psi

Answer

The air pressure must build to at least 100 psi before the vehicle is safe to move, ensuring adequate braking pressure is available.

Question 2

What does the low air pressure warning device activate at?

Accepted Answer

60 psi or below

Answer

The low air pressure warning (buzzer or light) activates when reservoir pressure drops to 60 psi or below, alerting the driver.

Question 3

What happens if air pressure drops below approximately 20–45 psi in a spring brake system?

Accepted Answer

The spring brakes apply automatically

Answer

Spring brakes apply automatically when reservoir air pressure drops too low, preventing the vehicle from moving without adequate brake pressure.

Question 4

What is the purpose of the air dryer in an air brake system?

Accepted Answer

To remove moisture and contaminants from compressed air

Answer

The air dryer removes moisture and oil from the compressed air before it enters the reservoirs, preventing corrosion and freeze-ups.

Question 5

During a pre-trip inspection, what should the static air leakage test measure?

Accepted Answer

Air pressure drop over one minute with engine off and brakes applied

Answer

The static leakage test checks that pressure does not drop more than 4 psi per minute (single vehicle) with brakes applied and engine off.

SGI - Saskatchewan Government Insurance Corporation Practice Test