EN ISO 15112:2014

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and units
5 General principles
6 Gas measurement
7 Energy determination
8 Strategy and procedures
9 Assignment methods
10 Calculation of energy quantities
11 Accuracy on calculated energy
12 Quality control and quality assurance
Annex A (informative) - Main instruments and
        energy-determination techniques
Annex B (informative) - Different possible patterns in the
        change of the calorific value
Annex C (informative) - Volume conversion and volume-to-mass
        conversion
Annex D (informative) - Incremental energy determination
Annex E (informative) - Practical examples for volume conversion
        and energy quantity calculation
Annex F (informative) - Practical examples for averaging the
        calorific value due to different delivery situations
Annex G (informative) - Ways of determining substitute values
Annex H (informative) - Plausibility check graphical example
Annex I (informative) - Uncorrected data, bias correction and
        final result graphical example
Annex J (informative) - Single-reservoir calorific value
        determination
Bibliography

ISO 15112:2011 provides the means for energy determination of natural gas by measurement or by calculation, and describes the related techniques and measures that are necessary to take. The calculation of thermal energy is based on the separate measurement of the quantity, either by mass or by volume, of gas transferred and its measured or calculated calorific value. The general means of calculating uncertainties are also given.Only systems currently in use are described.ISO 15112:2011 applies to any gas-measuring station from domestic to very large high-pressure transmission.New techniques are not excluded, provided their proven performance is equivalent to, or better than, that of those techniques referred to in ISO 15112:2011.Gas-measuring systems are not the subject of ISO 15112:2011.