During an air brake check, you should know that air pressure should build from 85 to 100 psi within what timeframe?

In a typical AIR PRESSURE BUILD-UP test for dual air systems, pressure should build from 85 to 100 psi within about 45 seconds. CDL air brakes pre-trip. This checks that the compressor is building air at an adequate rate. If pressure builds too slowly, the system may not maintain adequate air during operation (a safety concern). The pre-trip air brake test also includes checking the low-pressure warning, the spring brake activation point, and testing for air leaks (the system shouldn't lose more than a set amount of pressure per minute). Knowing the build-up rate test is commonly tested.