There are many regions in the United States that currently do not meet the National Ambient Air Quality Standards, and consequently, air quality management districts in such regions are compelling commercial motor vehicle (CMV) fleet operators to use clean-burning alternative fuels instead of diesel. The most commonly available alternative fuel for commercial vehicles is natural gas (i.e., either compressed or liquefied natural gas). To accommodate and facilitate the use of natural gas by CMVs, there is a need for lay persons, such as fleet managers, commercial drivers, fueling technicians, and mechanics to have a set of guidelines for safe operation and maintenance of CMVs using natural gas as alternative fuel. In addition, there is a need to assess the revisions needed to update the FMCSRs for accommodating natural gas as alternative fuel. Also, there is a need to evaluate and recommend the changes necessary to the North American Standard Level 1 Inspection procedures for commercial vehicles using natural gas as a fuel.