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CNG Cylinder Safety 

Education, Outreach, and Next Steps

Natural Gas Vehicle Technology Forum

Brookhaven National Laboratory, Upton, New York

Mark Smith and Alex Schroeder

January 14th, 2014

NREL/PR-5400-61482
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Overview and Objectives

Project Participants

Presentation and Discussion Objectives

• Describe CNG Cylinder Safety Project Objectives 

• Get Feedback from NGVTF on CNG Cylinder Education and 

Outreach Efforts, Best Practices and Next Steps
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Project Background

Background •NGV2 cylinder safety standards 

promulgated in 1994 provide for 15, 

20, and 25-year lifetimes 

•No formal tracking to ensure cylinders 

are properly disposed of at end of life 

Example State Regulations •Texas – Requires verification of 

cylinder age at time of vehicle 

inspection, which occurs annually •Utah – State Patrol includes end of life 

as part of 3 year/36,000 mile 

inspection program •Inspection legislation introduced in CA 

in 2013, considered in other states
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CNG Cylinder Safety Project Objectives

• Development of material explaining NGV2 standards and post 

collision best practices

• Developed material explaining how to “defuel” a damaged or 

expired cylinder

• Project roll-out at Natural Gas Vehicle Task Force (NGVTF) 

• Various presentations at conferences

Cylinder Awareness and Safety 

Monitoring Outreach

• Determination that no database of cylinder lifetimes exists in the 

industry and there is no mechanism in place to do so, particularly 

for conversions

• Development of web materials and database to begin collecting 

data on cylinders

• Outreach to stakeholders on strategies for cylinder data collection 

Legacy Cylinder ID and 

Documentation

• Project discussion at the NGVTF

National Coordination

• Provide technical support as needed/requested

Technical Support

Project Objectives

• Identify any existing 

information and/or 

datasets on NGV cylinders

• Create educational 

materials for NGV owners 

and support industries on 

cylinder safety

• Engage with stakeholders 

to get feedback and 

create awareness

• Develop a system to begin 

collecting relevant data 

on CNG cylinders
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Education and Date Collection from the Public

• One-Stop Portal for 

Information Related to CNG 

Cylinder Safety and End of 

Life Regulations

• Voluntary Web-based Data 

Collection of CNG Cylinders

Website Ready to Launch Pending OMB approval 

• Outreach with Stakeholders 

to Promote Awareness and 

Encourage Data Collection 
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What Will NREL do With the Data?

Data is intended to inform 

educational efforts and will 

be non-attributable

 

• Inform accident prevention 

outreach and education 

efforts

• Primary audience for 

outreach is not large fleets, 

but resale and secondary 

markets

• Will not be used as an 

enforcement or regulatory 

tool
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Questions for Discussion 

How is this best communicated to NGV stakeholders at large?

What do you feel is the best approach for addressing cylinder end of life?

In what situation do you believe there is the greatest risk of CNG cylinder failure due to 

“expired” cylinders? 

Do you believe that a majority of industry actively manages their CNG cylinder inventory 

for end of life? 

How big of an issue do you perceive CNG cylinder liabilities as being?