Air Brake Coach
System partsQuestion 16 of 116

What damages the desiccant in an air dryer?

  1. Pure alcohol
  2. Dry air
  3. Cold air
  4. A full supply tank
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Correct answer: Pure alcohol

Pure alcohol damages the desiccant. Do not add alcohol ahead of the air dryer.

Source: Air Brake Manual: A Guide for Instructors (Government of Alberta, Alberta Transportation, March/April 2012), Module 3: Supply circuit, page 44

Practice system parts

Questions last reviewed: 18 October 2026