Question

With a fully charged air system typically 125 psi. Turn off the engine and release the parking brake and time the air pressure drop.

A) 2 psi per minute
B) 3 psi per minute
C) 4 psi per minute
D) 5 psi per minute

Answer 1

The permissible air pressure drop in a commercial vehicle air brake system after turning off the engine and releasing the parking brake is not more than 3 psi per minute, according to Federal Motor Carrier Safety Regulations.

Step-by-step explanation:

The permissible air pressure drop in an air brake system when the engine is turned off and the parking brake is released. This situation is about commercial vehicle air brake systems and it is a safety standard in the transportation industry.

While the actual answer to this question, which pertains to the rate of air pressure drop allowed, is not provided in the provided information, the Federal Motor Carrier Safety Regulations (FMCSR) specify that for a combination vehicle (tractor-trailer), the loss rate should not be more than 3 psi per minute with the engine off and the brakes released.

Answer 2

Under FMCSA guidelines, with a fully charged air system typically 125 psi, turn off the engine release the parking brake, and time the air pressure drop, for a single vehicle the air pressure should not drop more than 2 psi per minute (option A).

Step-by-step explanation:

The question appears to address the topic of air pressure in vehicle tires and how it decreases over time when the vehicle is not running. The specific test it refers to is likely part of commercial vehicle inspection guidelines or operations, where checking for air leaks in the braking system is critical.

To answer the question, the Federal Motor Carrier Safety Administration (FMCSA) guidelines suggest that for a single vehicle (trucks, buses, etc.), the air pressure should not drop more than 2 psi per minute with the engine turned off and the parking brake released. However, it should be noted that specific regulations might vary by location or over time, so it's always best to consult the most current guidelines or legal requirements for commercial vehicle operations.

Thus, from the provided options, A) 2 psi per minute is the correct answer for the air pressure drop in a properly maintained air system.

Your question is incomplete, but most probably your full question was

With a fully charged air system typically 125 psi, turn off the engine release the parking brake, and time the air pressure drop, for a single vehicle the air pressure should not drop more than ___________.

A) 2 psi per minute

B) 3 psi per minute

C) 4 psi per minute

D) 5 psi per minute