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

60 psi

Answer

50 psi

Answer

120 psi

Question 2

What does the low air pressure warning device activate at?

Accepted Answer

60 psi or below

Answer

100 psi

Answer

80 psi

Answer

40 psi

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

The service brakes apply automatically

Answer

Nothing happens until the driver brakes

Answer

The air dryer activates

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

To increase brake pressure

Answer

To cool the air reservoirs

Answer

To power the spring brakes

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

Air pressure at full engine speed

Answer

Time for pressure to build from 0 to 100 psi

Answer

Pressure at each individual wheel

Question 6

What is brake fade, and when does it occur?

Accepted Answer

Reduction in braking effectiveness due to heat build-up from overuse

Answer

Sudden brake failure due to moisture

Answer

Increase in brake pressure at high speeds

Answer

Vibration in the brake pedal