Cylinders are the most important component on board of NGVs.  Various issues have arisen from time to time relating to selection, installation, refueling and inspection.

When IANGV set up in 1986, one of the most important tasks was to promote the preparation of an international standard for the storage of natural gas on vehicles.  The preparation of this standard took many years and was eventually published ISO 11439 in 2000.  This standard has recently been revised and the draft is being circulated.  Any IANGV member (including members of regional or national associations) who wish to review the draft revised may request a copy by sending an email to This e-mail address is being protected from spambots. You need JavaScript enabled to view it . 

Another international standard of importance is ISO 19078 which relates to the inspection of the cylinder installation and subsequent requalification.  (See www.iangv.org/international-standards-a-k.html#IS for all relevant ISO standards)

An incident was recently reported from Thailand.  A truck with 7 cylinders was refilling and 1 cylinder exploded.  7 people received only minor injuries.  Initial reports state that the fiberglass wrapping of the Type 2 cylinder had been damaged.  This incident highlights 2 important issues – inspection and inspection.  Cylinders need to be regularly inspected, at least as frequently as required by the relevant country regulations and secondly, following any accident or untoward event that could have affected the cylinder.  For instance, there have been cylinder incidents resulting from spilt battery acid – nothing whatever to do with the cylinder itself.  Some cylinder incidents have been hugely damaging to people and property.

On the IANGV website are there is a section relating to incidents with NGVs.  The information in this section is available for the use of IANGV members only.  In the proceedings of the IANGV conferences, there are various papers which relate to cylinders.  These too are available for downloading from www.iangv.org.

Recognizing that there is a need to have a good understanding of all aspects of cylinders over the total life of a cylinder, IANGV published a handbook entitled “General Information for end users and/or installation workshops and qualified registered personnel.”  The handbook is available for downloading.

The aim of IANGV has been to get harmonized standards and regulations.  ISO is seen as the main organization with responsibility for preparation of the international standards.  Ideally all regulations and all national standards would derive from the ISO standards.  In January 2007, a Roundtable on Harmonisation of Regulations Codes was convened to go over the issues and define what needed to be done.  The ISO report arising from the Roundtable can be viewed here. Many of the recommendations contained in their report are now being or have been implemented.

We are at a situation where there are ISO standards for most parts of the NGV system or the gaps are now being filled.  It is important that the standards mentioned above are used internationally as the basis for regulatory systems in the various countries which are implementing NGV programs.