During testing, the hold time for 85-100 psi in a properly functioning dual air system should be what duration?

During testing, the hold time for 85-100 psi in a properly functioning dual air system should be what duration?

• A. 15 seconds
• B. 45 seconds
• C. 60 seconds
• D. 90 seconds

Answer: (B)

In a dual air system, you’re checking for leaks by watching how long the pressure can stay within a safe range after it’s built up. You inflate the system to between 85 and 100 psi, then hold it there for 45 seconds. If the pressure remains steady during that entire window, the system isn’t leaking through hoses, fittings, valves, or the reservoir lines, which means the two independent circuits will stay charged when you need braking. The 45-second duration is chosen because it’s long enough to reveal slow leaks but short enough to keep the test practical, whereas shorter times might miss small leaks and longer times aren’t necessary for the test procedure.

In a dual air system, you’re checking for leaks by watching how long the pressure can stay within a safe range after it’s built up. You inflate the system to between 85 and 100 psi, then hold it there for 45 seconds. If the pressure remains steady during that entire window, the system isn’t leaking through hoses, fittings, valves, or the reservoir lines, which means the two independent circuits will stay charged when you need braking. The 45-second duration is chosen because it’s long enough to reveal slow leaks but short enough to keep the test practical, whereas shorter times might miss small leaks and longer times aren’t necessary for the test procedure.