For dual-air braking systems, the pressure needs to increase to _________.

For dual-air braking systems, the pressure needs to increase to 85-100 psi within 45 seconds. This refers to the pressure build-up time required for the system to reach the specified operating pressure range after the engine is started or after the system is depleted of air. It is important for the system to reach this pressure range within the designated time to ensure proper brake functionality and responsiveness.