Question

An air brake system safety relief valve opens at about:

a. 20 to 45 psi.
b. 120 psi.
c. 150 psi.

Answer 1

The safety relief valve in an air brake system opens when the pressure exceeds a certain level. The correct answer is a. 20 to 45 psi.

Step-by-step explanation:

The safety relief valve in an air brake system opens when the pressure exceeds a certain level to release the excess pressure and prevent damage to the system. In this case, the options are:

a. 20 to 45 psi

b. 120 psi

c. 150 psi

The correct answer is a. 20 to 45 psi. This means that the safety relief valve will open when the pressure in the system exceeds 20 psi but is below 45 psi.