The Standard is freely available on the Internet to be used as widely as possible, without charge, by anyone who can benefit from it. The only condition of use is that the copyright of the author be acknowledged in any application where it is deployed. The author takes no responsibility for accuracy or completeness of this Standard or for any consequential loss resulting from its use. It may be enhanced and extended as required although it is hoped that any modifications will be notified to the author for consideration for inclusion within future versions of the standard itself.