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CDL · Inspecting Tank Vehicles

What is a 'vapor recovery system' on a fuel tanker and why does it need inspection?

Correct answer

A system that captures fuel vapors during loading/unloading to prevent atmospheric release; it must be inspected for proper valve operation and line integrity — failed vapor recovery can cause dangerous vapor accumulation near ignition sources

  1. A A device that improves fuel economy
  2. B A system that captures fuel vapors during loading/unloading to prevent atmospheric release; it must be inspected for proper valve operation and line integrity — failed vapor recovery can cause dangerous vapor accumulation near ignition sources
  3. C Only relevant in cold weather
  4. D Only on food-grade tankers

Why this is the answer

VAPOR RECOVERY SYSTEMS are required on petroleum fuel tankers under EPA regulations. During loading and unloading, displaced vapors from the tank would otherwise escape to atmosphere — creating both air pollution and fire/explosion hazard (fuel vapors are heavier than air and pool at ground level). The vapor recovery system captures displaced vapors and routes them back to the storage tank. Pre-trip inspection: verify vapor recovery valves open and close correctly; check hoses for cracks; verify coupling points seal tightly; ensure the system is in the position required for transport (typically closed during movement).
Source: FMCSA CDL Manual, Chapter 10, Tank Vehicles, Vapor Recovery

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