Air Brake Coach
InspectionQuestion 77 of 116

How long must the compressor take to build air from 50 to 90 PSI during the pre-trip?

  1. 8 minutes or less
  2. 30 seconds or less
  3. 15 minutes or less
  4. 3 minutes or less
Show answer

Correct answer: 3 minutes or less

The build-up test is 50 to 90 PSI (345 to 621 kPa) within 3 minutes.

Source: Air Brake Manual: A Guide for Instructors (Government of Alberta, Alberta Transportation, March/April 2012), Air Brake Practical Test (DPLS0003): Supply circuit, page 123

Practice inspection

Questions last reviewed: 18 October 2026