BS EN ISO 13686:2013

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols, abbreviations and units
5 Quality designation parameters
6 Sampling
Annex A (informative) - Introduction to informative annexes
Annex B (informative) - German Regulation Code of Practice
        DVGW G 260:2008, Extract of the relevant parts
        for natural gases
Annex C (informative) - European Standard EN 437 "Test gases,
        test pressures and categories of appliances"
Annex D (informative) - Interchangeability AGA index method
Annex E (informative) - British Gas Hydrocarbon Equivalence
        Method
Annex F (informative) - Weaver index method
Annex G (informative) - French method for determining gas
        interchangeability (Delbourg method) (guide for
        determining the interchangeability of second
        family gases)
Annex H (informative) - Spanish regulation code (Detail
        Protocol-01 - Measurement) - Extract of the relevant
        parts for natural gases
Annex I (informative) - Harmonization of gas property data
        for cross-border transportation
Bibliography

Defines the parameters required to describe finally processed and, where required, blended natural gas.

This International Standard specifies the parameters required to describe finally processed and, where required, blended natural gas. Such gas is referred to subsequently in this text simply as “natural gas”.

The main text of this International Standard contains a list of these parameters, their units and references to measurement standards. Informative annexes give examples of typical values for these parameters, with the main emphasis on health and safety.

In defining the parameters governing composition, physical properties and trace constituents, consideration has also been given to existing natural gases to ensure their continuing viability.

The question of interchangeability is dealt with in AnnexA (see ClauseA.2).