ISO 19230:2020

INTERNATIONAL ISO
STANDARD 19230
First edition
2020-11
Gas analysis — Sampling guidelines
Analyse des gaz — Lignes directrices pour le prélèvement des
échantillons
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Sampling plan . 5
5 Sampling classification . 6
5.1 Sampling classification of gases . 6
5.2 Sampling classification of liquefied gas . 7
6 Technical specifications . 8
6.1 Overview . 8
6.2 General considerations for gas sampling . 8
6.2.1 Adsorption, reaction and permeation of sampling system . 8
6.2.2 Leaks and atmospheric diffusion in the sampling system . 8
6.2.3 Leak testing of the sampling system . 8
6.2.4 Purging of the sampling system . 9
6.2.5 Homogeneity of gas .12
6.2.6 Inert-gas purging .12
6.3 Possible condensation during compressed gas sampling.12
6.4 Main considerations for liquefied gas sampling .13
6.5 Samples that are not feasible in containers or cannot be used for analysis directly .13
7 Safety guidance in sampling .13
7.1 Overview .13
7.2 General recommendation .13
7.3 Specific recommendation for sampling a certain substance .14
8 Sampling devices .14
8.1 General provision .14
8.2 Sample container .14
8.2.1 Sample container material .14
8.2.2 Structure of sample container .16
8.2.3 Volume of sample container .18
8.3 Sample probe .18
8.4 Pressure reducer and flow controller .19
8.5 Sample pump .19
8.6 Sample line .19
8.6.1 Material of sample line .19
8.6.2 Length and diameter of sample line .20
8.7 Connecters and seals .20
8.8 Cleaning and drying of the sampling device .20
8.9 Connection of sampling devices .20
9 Sampling .21
9.1 Sampling method block diagram .21
9.1.1 Overview .21
9.1.2 Block diagram of compressed gas sampling method .21
9.1.3 Block diagram of liquefied gas sampling method .21
9.2 Quality assessment of the sampling system .22
9.3 Sampling from the gaseous phase and sampling after evaporation of liquefied gas .22
9.4 Direct sampling .23
9.4.1 General provisions.23
9.4.2 Direct sampling of gas in pressure receptacles .23
9.4.3 Direct sampling of gas in pipelines .23
9.5 Indirect sampling .23
9.5.1 Indirect sampling of gas in pressure receptacles .23
9.5.2 Indirect sampling of gas in pipelines .24
9.5.3 Leakage test of sample container .25
9.5.4 Storage of samples . . .25
9.6 Sampling records .25
Annex A (informative) Examples of estimation of the purging time and purging cycles for
sampling system . .26
Annex B (informative) Direct sampling for gas in pressure receptacles .27
Annex C (informative) Direct sampling of gas in pipelines .30
Annex D (informative) Fill-empty sampling method .32
Annex E (informative) Evacuated-container sampling .34
Annex F (informative) Evacuated-system sampling .39
Annex G (informative) Indirect sampling using floating piston cylinders .41
Bibliography .43
iv © ISO 2020 – All rights reserved

Foreword
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This document was prepared by Technical Committee ISO/TC 158, Analysis of gases.
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