Certified CNG Cylinder Inspectors Needed in United States and Worldwide

Compressed natural gas (CNG) has long been utilized as a motor vehicle fuel. Natural gas currently is compressed into vehicle storage cylinders up to 3600 psi, with 5000 psi cylinders possible in the future. With more than 150,000 CNG vehicles on the roads in the United States and worldwide vehicles reaching more than 5 million, CNG cylinders have proven to be a safe method of natural gas fuel storage. Consequently, as the number of CNG vehicles grows, there is a pressing need for the number of certified CNG cylinder inspectors to increase.

Tools used during CNG cylinder inspection include natural gas leak detectors and micrometers. NAFTC Photo

In order to ensure a positive safety record of storing CNG on board motor vehicles in the United States, the U.S. Department of Transportation requires that all CNG cylinders be inspected once every three years or 36,000 miles (whichever comes first) and sometimes more often under special circumstances. More information may be found at www.cleanvehicle.org. Currently there are two common types of inspection for CNG motor vehicle cylinders. The first is a general visual inspection, which can be performed by any service technician, filling attendant, vehicle owner, etc., who can look for gross signs of damage; this type of inspection may be performed any time during the life of the cylinder with no required inspection schedule. If damage is found during a general visual inspection, contact a certified cylinder inspector immediately. Certified cylinder inspectors may be found following the link on CSA America Web site (http://webext.csa.ca/cng/cngmain.asp#searchinspector).

Students learn the CNG cylinder inspection process during one of NAFTC’s CNG Cylinder Safety and Inspection Certification courses. NAFTC Photo

The second type of inspection is to be performed by a certified cylinder inspector. The certified inspector is trained to perform a detailed cylinder inspection by attending a two-day training course and passing a written test provided by CSA America. CSA America is a standards writing body in the United States for appliances and accessories fueled by natural, liquefied petroleum, and hydrogen gases. The detailed inspection may be performed by any person who takes a CNG cylinder course and passes the certification test. A list of training courses may be found at www.cleanvehicle.org/technology/cylinder.shtml.

The NAFTC’s CNG Cylinder Safety Inspection and Certification course provides technicians, fleet managers, and automotive instructors the opportunity to learn how to inspect CNG cylinders and become a certified cylinder inspector through CSA International. During this two-day course, participants learn about the four different types of CNG cylinders and specific procedures required to inspect them. The laws and regulations for each type of cylinder are thoroughly discussed. Additional topics included in this course are proper cylinder mounting techniques and proper cylinder venting procedures. Participants gain hands-on experience by inspecting previously-used CNG cylinders and by practicing completion of inspection forms. Tools used during the inspection process include natural gas leak detectors and micrometers, and the numerous training aids available in this course are items such as cylinders that have been cut open to show their construction, four CNG-powered vehicles, a CNG cylinder venting device, and a CNG compressor filling unit.

Course participants will be provided with a course manual and will have the opportunity to take the certification test on the second day. The tests are sent to CSA International to be graded, and after successfully passing the exam, CSA will provide inspection forms and pass/fail stickers to be used in the cylinder inspection process. CSA will also add the individual’s name to a national registry of inspectors. Certification can be renewed each year directly through CSA without having to retake the course. More information can be found at www.naftc.wvu.edu/curriculum/courses/
description/cylinder.html.

A scholarship is available through the Clean Vehicle Education Foundation (CVEF) to qualified individuals wishing to take the Cylinder Safety Inspection and Certification Course. The scholarship covers both the course fee and CSA test fee, although the scholarship funding requires that the participant successfully pass the test. The NAFTC encourages anyone taking this course to apply for the scholarship. The scholarship is available at www.cleanvehicle.org/technology/cylinder.shtml#5.

In a related story, the NAFTC is part of a committee that will work with CSA America, Inc., to update the CNG cylinders inspection and inspector certification process. Updates should be announced sometime in the upcoming months.

In addition to the cylinder inspection course, participants who wish to learn more about CNG vehicle maintenance might be interested in other courses the NAFTC offers, including “Light-Duty Natural Gas Vehicles"and “Heavy-Duty Gaseous Fuel Applications" (www.naftc.wvu.edu/curriculum/courses.html).