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Course: Leak Detection in Natural Gas and Propane CMVs

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The Federal Motor Carrier Safety Administration (FMCSA) has developed a training course on leak detection in commercial motor vehicles (CMVs) fueled by natural gas (compressed or liquefied) and propane (also known as liquefied petroleum gas).

The fuel system is one of the 14 safety-critical systems of a CMV. A defect in a safety-critical system, such as a leak in the fuel system, is grounds for placing a vehicle out of service (OOS). Unlike a conventional diesel fuel leak, a natural gas leak may not be detected by the human senses for several reasons.  Thus, a combustible gas detector or bubble leak test is necessary to confirm a leak of natural gas or propane. The training objectives of this course are to identify vehicles powered by natural gas or propane, become familiar with the unique characteristics and leak properties of these  fuels, list the major components of each type of fuel system and the places most likely to leak, detect fuel leaks, and know what to do if a vehicle has a fuel leak.   The last training objective addresses how to use a combustible gas detector to confirm a fuel leak.

While this course was designed for CMV inspectors, it may be useful to owners or operators of natural gas and propane CMVs, or others who may be exposed to these types of vehicles.

This course, available at Leak Detection in Natural Gas and Propane Commercial Motor Vehicles Course: Manuscript, is approximately 2 hours in length and includes two modules with content, graphic displays, and a video demonstration of selected detectors. There will be knowledge checks throughout the training. A text-only manuscript of the training is available for download in the "Related Documents" section of this page.

NOTE: This training application functions optimally when viewed in Google Chrome or Safari. Certain functionalities related to the interactive knowledge checks and post-quiz review may be limited in Internet Explorer or Firefox.