Gas supply systems - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields

This standard specifies procedures and practices which are safe and environmentally acceptable. It covers the functional recommendations for design, construction, testing, commissioning, operation and maintenance of underground gas storage facilities in oil and gas fields up to and including the wing valve of the wellhead. The necessary surface facilities for underground gas storage are described in prEN 1918-5.

Gasversorgungssysteme - Untertagespeicherung von Gas - Teil 2: Funktionale Empfehlungen für die Speicherung in Öl- und Gasfeldern

Diese Norm legt Verfahren und Praktiken fest, die sicher und umweltverträglich sind. Sie umfaßt die funktionalen Empfehlungen für Planung, Bau, Prüfung, Inbetriebnahme, Betrieb und Instandhaltung von Untertagespeichern für Gas in Öl- und Gasfeldern bis zum Bohrlochkopf einschließlich des Seitenschiebers. Die erforderlichen übertägigen Anlagen für einen Untertagespeicher für Gas werden in prEN 1918-5 beschrieben.

Système d'alimentation en gaz - Stockage souterrain de gaz - Partie 2: Recommandations fonctionnelles pour le stockage en gisements de pétrole et de gaz

La présente norme spécifie les procédures et les pratiques qui sont acceptables pour la sécurité et l'environnement. Elle décrit les recommandations fonctionnelles pour la conception, la construction, les essais, la mise en service, l'exploitation et la maintenance des stockages souterrains en gisements de pétrole et de gaz jusqu'au robinet latéral de la tête de puits inclus. Les installations de surface qui sont nécessaires pour un stockage souterrain de gaz sont décrites dans la prEN 1918-5.

Sistemi oskrbe s plinom - Podzemna plinska skladišča - 2. del: Funkcionalna priporočila za skladiščenje na naftnih in plinskih poljih

General Information

Status: Withdrawn
Publication Date: 17-Feb-1998
Withdrawal Date: 20-Jan-2026

ICS: 75.200 - Petroleum products and natural gas handling equipment

Technical Committee: CEN/TC 234 - Gas infrastructure
Drafting Committee: CEN/TC 234/WG 4 - Gas underground storage

Current Stage: 9960 - Withdrawal effective - Withdrawal
Start Date: 23-Mar-2016
Completion Date: 21-Jan-2026

Directive: 93/38/EEC - Procurement procedures of entities operating in the water, energy, transport and telecommunications sectors

Mandate: M/017 - Standardization mandate to CEN in the field of equipment and installation for the transmission and distribution of gas

Ref Project: SIST EN 1918-2:1999 - Gas supply systems - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields

Relations

Replaced By: EN 1918-2:2016 - Gas infrastructure - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields
Effective Date: 30-Mar-2016

Standard

EN 1918-2:1999

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Frequently Asked Questions

What is EN 1918-2:1998?

EN 1918-2:1998 is a standard published by the European Committee for Standardization (CEN). Its full title is "Gas supply systems - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields". This standard covers: This standard specifies procedures and practices which are safe and environmentally acceptable. It covers the functional recommendations for design, construction, testing, commissioning, operation and maintenance of underground gas storage facilities in oil and gas fields up to and including the wing valve of the wellhead. The necessary surface facilities for underground gas storage are described in prEN 1918-5.

What is the scope of EN 1918-2:1998?

What ICS categories does EN 1918-2:1998 belong to?

EN 1918-2:1998 is classified under the following ICS (International Classification for Standards) categories: 75.200 - Petroleum products and natural gas handling equipment. The ICS classification helps identify the subject area and facilitates finding related standards.

What standards are related to EN 1918-2:1998?

EN 1918-2:1998 has the following relationships with other standards: It is inter standard links to EN 1918-2:2016. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.

Is EN 1918-2:1998 a harmonized European standard?

EN 1918-2:1998 is associated with the following European legislation: EU Directives/Regulations: 93/38/EEC; Standardization Mandates: M/017. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.

How can I access EN 1918-2:1998?

EN 1918-2:1998 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.

Standards Content (Sample)

EN 1918-2:1999

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.QNFLRQDOQDGasversorgungssysteme - Untertagespeicherung von Gas - Teil 2: Funktionale Empfehlungen für die Speicherung in Öl- und GasfeldernSysteme d'alimentation en gaz - Stockage souterrain de gaz - Partie 2: Recommandations fonctionnelles pour le stockage en gisements de pétrole et de gazGas supply systems - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields75.200Petroleum products and natural gas handling equi
...

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CEN

EN 12186:2025(Main)

Gas infrastructure - Gas pressure control stations for transmission and distribution - Functional requirements

kSIST FprEN 12186:2025

This document specifies the functional requirements relevant for design, materials, construction, testing, operation and maintenance of gas pressure control stations to ensure their reliability in terms of safety of the station itself and the downstream system and continuity of service.
This document is applicable for gas pressure control stations which are part of gas transmission or distribution systems for hydrogen, and hydrogen rich, and methane rich gases. Additional requirements in the case of gases heavier than air and/or toxic or corrosive gases are not covered by this document.
This document does not apply to gas pressure control stations in operation prior to the publication of this document. However, Annex D of this document can be used as guidance for the evaluation of stations in operation prior to the publication of this document, regarding the change of the type of gas, e.g. repurposing for the use with hydrogen.
The stations covered by this document have a maximum upstream operating pressure, which does not exceed 100 bar. For higher maximum upstream operating pressures, this document can be used as a guideline.
If the inlet pipework of the station is a service line and the maximum upstream operating pressure does not exceed 16 bar and the design flow rate is equal to 2000 kW based on the gross calorific value or less, EN 12279 applies.
This document contains the basic system requirements for gas pressure control stations. Requirements for individual components (valves, regulators, safety devices, pipes, etc.) or installation of the components are contained in the appropriate European Standards.
NOTE For combined control and measuring stations, the additional requirements of EN 1776 can apply.
The requirements in this document do not apply to the design and construction of auxiliary facilities such as sampling, calorimetering, odorization systems and density measuring. These facilities are covered by the appropriate European Standards, where existing, or applicable national standards.
The requirements of this document are based on good gas engineering practice under conditions normally encountered in the gas industry. Requirements for unusual conditions cannot be specifically provided for, nor are all engineering and construction details prescribed.
The objective of this document is to ensure the safe operation of such stations. This does not, however, relieve all concerned of the responsibility for taking the necessary care and applying effective quality and safety management during the design, construction, operation and maintenance.

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CEN

EN 12583:2022+A1:2024(Main + Amendment)

Gas Infrastructure - Compressor stations - Functional requirements

SIST EN 12583:2022+A1:2025

This document describes the specific functional requirements for the design, construction, operation, maintenance and disposal activities for safe and secure gas compressor stations.
This document applies to new gas compressor stations with a Maximum Operating Pressure (MOP) over 16 bar and with a total shaft power over 1 MW. For existing compressor stations, this document applies to new compressor units. Where changes/modifications to existing installations or gas composition take place, due account can be taken of the requirements of this document.
This document does not apply to gas compressor stations or compressor units operating prior to the publication of this document. For existing sites this document can be used as guidance.
The purpose of this document is to:
—   ensure the health and safety of the public and all site personnel;
—   cover environmental issues;
—   avoid incidental damage to nearby property; and
—   open the gas infrastructure to accommodate renewable gases, including a possible design for hydrogen.
This document specifies common basic principles for the gas infrastructure. Users of this document are expected to be aware that more detailed national standards and/or codes of practice can exist in the CEN member countries.
This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of conflicts in terms of more restrictive requirements in national legislation/regulation with the requirements of this document, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts). CEN/TR 13737 (all parts) gives:
—   clarification of all legislations/regulations applicable in a member state;
—   if appropriate, more restrictive national requirements;
—   a national contact point for the latest information.
This document does not apply to:
—   off-shore gas compressor stations;
—   gas compressor stations for compressed gas filling-stations;
—   customer installations downstream of the point of custody transfer;
—   design and construction of driver packages (see Annex C);
—   mobile compressor equipment.
For supplies to utility services such as small central heating boilers reference is made to EN 1775.
Figure 1 shows a schematic representation of compressor stations in a gas infrastructure. For further information refer to Annexes A, B, C, D, E and F.
[Figure 1]

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CEN

EN 17928-1:2024(Main)

Gas infrastructure - Injection stations - Part 1: General requirements

SIST EN 17928-1:2025

This document establishes the functional requirements for stations for the injection of biomethane, substitute natural gas (SNG) and hydrogen into gas transmission and distribution systems operated with gases (natural gas, biomethane, SNG, hydrogen, gas mixtures) in accordance with European technical rules that ensure the interoperability of systems.
Figure 1 describes the general approach including all the relevant functions that can be installed in different configurations. The injection of Hydrogen is covered separately in EN 17928-3:2024.
This document also applies to refeeding stations that feed such gases back into upstream gas supply networks; see Figure 2.
This document represents the state of the art at the time of its preparation.
This document does not apply to injection stations operating prior to the publication of this document.
This document specifies common basic principles for gas infrastructure. Users of this document are expected to be aware that more detailed national standards and/or codes of practice can exist in the CEN member countries. This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of terms of additional requirements in national legislation/regulation than in this document, CEN/TR 13737 (all parts) illustrates these terms.
CEN/TR 13737 (all parts) gives:
—   legislation/regulations applicable in a member state;
—   if appropriate, more restrictive national requirements;
—   a national contact point for the latest information.

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CEN

EN 17928-2:2024(Main)

Gas infrastructure - Injection stations - Part 2: Specific requirements regarding the injection of biomethane

SIST EN 17928-2:2025

This document establishes specific functional requirements for injection stations for biomethane into gas transmission and distribution systems operated with gases of the second gas family in accordance with EN 437 in addition to the general functional requirements of EN 17928 1:2024.
This document represents the recommendations at the time of its preparation. This document does not apply to injection stations operating prior to the publication of this document.
This document complements EN 17928 1:2024 by specifying the technical safety requirements to be observed in respect of the chemical and physical properties of biomethane.
This document specifies common basic principles for gas infrastructure. Users of this document are expected to be aware that more detailed national standards and/or codes of practice can exist in the CEN member countries.
This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of terms of additional requirements in national legislation/regulation than in this document, CEN/TR 13737 (all parts) illustrates these terms.
CEN/TR 13737 (all parts) gives:
—   legislation/regulations applicable in a member state;
—   if appropriate, more restrictive national requirements;
—   a national contact point for the latest information.

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EN 17928-3:2024(Main)

Gas infrastructure - Injection stations - Part 3: Specific requirements regarding the injection of hydrogen

SIST EN 17928-3:2025

This document establishes specific functional requirements of stations for the injection of hydrogen into transmission and distribution systems for fuel gases (natural gas, biomethane, SNG, hydrogen, fuel gas mixtures, etc.; see Figure 1) in accordance with European technical rules that ensure the interoperability of systems in addition to the general functional requirements of EN 17928 1:2024.
This document complements EN 17928 1:2024 by specifying the technical safety requirements to be observed with respect to the chemical and physical properties of hydrogen.
It furthermore complements the requirements on pipelines specified in EN 12007 3 and EN 1594 by describing the specific requirements with respect to hydrogen.
Additionally, it explains how to handle hydrogen measurements during the course of injection.
Dedicated requirements for the technical equipment of the gas transmission and distribution network for mixing hydrogen as an additive gas into the gas flow after the injection station are not covered by this document. However, requirements for the resulting gas mixture and the related coordination and interfaces between station and network operation are specified in this document.
This document represents the recommendations at the time of its preparation. This document does not apply to injection stations operating prior to the publication of this document.
This document specifies common basic principles for gas infrastructure. Users of this document are expected to be aware that more detailed national standards and/or codes of practice can exist in the CEN member countries. This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of terms of additional requirements in national legislation/regulation than in this document, CEN/TR 13737 (all parts) illustrates these terms.
CEN/TR 13737 (all parts) gives:
—   legislation/regulations applicable in a member state;
—   if appropriate, more restrictive national requirements;
—   a national contact point for the latest information.

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CEN

EN 1594:2024(Main)

Gas infrastructure - Pipelines for maximum operating pressure over 16 bar - Functional requirements

SIST EN 1594:2024

This document describes the functional requirements for pipelines for maximum operating pressure over 16 bar. This document also describes the mechanical requirements for pipework in stations with a maximum operating pressure greater than 16 bar.
NOTE 1   Welding requirements are described in EN 12732. Functional requirements for stations are given in EN 1776, EN 1918-5, EN 12186, and EN 12583.
This document is applicable for transporting gas via onshore high-pressure steel pipeline infrastructures, where the following applies:
-   onshore:
-   from the point where the pipeline first crosses what is normally accepted as battery limit between onshore and offshore, and that is not located within commercial or industrial premises as an integral part of the industrial process on these premises except for any pipelines and facilities supplying such premises;
-   pipeline system with a starting point onshore, also when parts of the pipeline system on the mainland subsequently cross fjords, lakes, etc.
-   high pressure: gas with a maximum operating pressure over 16 bar and a design temperature between −40 °C and 120 °C.
-   steel pipeline infrastructure: infrastructure consisting of pipeline components, such as pipes, valves, couplings and other equipment, restricted to components made of unalloyed or low alloyed carbon steel and joined by welds, flanges or mechanical couplings.
-   gas: non-corrosive natural gas, biomethane gas, hydrogen gas and mixtures of these gases where technical evaluation has ensured that operating conditions or constituents or properties of the gas do not affect the safe operation of the pipeline.
Gas infrastructures covered by this document begin after the gas producer's metering station.
NOTE 2   The functional demarcation of the pipeline system is usually directly after an isolating valve of the installation, but can differ in particular situations. The functional demarcation of the pipeline system is usually located on an isolating valve of the installation, but can differ in particular situations.
A schematic representation of pipelines for gas infrastructure is given in Figure 1.
This document can also be applied to the repurposing of existing pipelines.
[Figure 1 - Schematic representation of pipelines for gas supply over 16 bar]
This document specifies common basic principles for gas infrastructure. Users of this standard are expected to be aware that more detailed national standards and/or code of practice can exist in the CEN member countries.
This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of conflicts in terms of more restrictive requirements in national legislation/regulation with the requirements of this standard, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737.
CEN/TR 13737 gives:
-   clarification of all legislations/regulations applicable in a member state;
-   if appropriate, more restrictive national requirements;
-   a national contact point for the latest information.

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CEN

EN 17649:2022(Main)

Gas infrastructure - Safety Management System (SMS) and Pipeline Integrity Management System (PIMS) - Functional requirements

SIST EN 17649:2022

This document specifies requirements on the development and implementation of a Safety Management System (SMS) and a Pipeline Integrity Management System (PIMS). The SMS is applicable for system operators of a gas infrastructure. The PIMS is applicable for system operators of gas infrastructure with a maximum operating pressure (MOP) over 16 bar.
This document refers to all activities and processes related to safety aspects and performed by system operators of a gas infrastructure, including those activities entrusted to contractors. It includes safety-related provisions on operation of the gas infrastructure.
This document is applicable to infrastructure for the conveyance of processed, non-toxic and non-corrosive natural gas according to EN ISO 13686 and gases such as biomethane and hydrogen and to mixtures of these gases with natural gas.
This document covers also gases classified as group H, that are to be transmitted, injected into and from storages, distributed and utilized, as specified in EN 16726. For the requirements and test methods for biomethane at the point of entry into a natural gas network, reference is made to EN 16723-1.
This document can be applied for gas infrastructure conveying gases of the 3rd gas family as classified in EN 437 or for other gases such as carbon dioxide.
Specific requirements for occupational health and safety are excluded from this document. For these, other European and/or international standards, e.g. ISO 45001, apply.
This document specifies common basic principles for gas infrastructure. It is important that users of this document are expected to be aware that more detailed national standards and/or codes of practice exist in the CEN member countries. This document is intended to be applied in association with these national standards and/or codes of practice setting out the above-mentioned basic principles.
In the event of conflicts in terms of more restrictive requirements in national legislation/regulation with the requirements of this document, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts).
NOTE CEN/TR 13737 (all parts) contains:
- clarification of relevant legislation/regulations applicable in a country;
- if appropriate, more restrictive national requirements;
- national contact points for the latest information.

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EN 1918-5:2016(Main)

Gas infrastructure - Underground gas storage - Part 5: Functional recommendations for surface facilities

SIST EN 1918-5:2016

This European Standard covers the functional recommendations for the design, construction, testing, commissioning, operation, maintenance and abandonment of the surface facilities for underground gas storage (UGS), between the wellhead and the connection to the gas grid.
It specifies practices which are safe and environmentally acceptable.
For necessary subsurface facilities for underground storage, the relevant part of EN 1918-1 to EN 1918-4 applies.
In this context, "gas" is any hydrocarbon fuel:
-   which is in a gaseous state at a temperature of 15 °C and under a pressure of 0,1 MPa (this includes natural gas, compressed natural gas (CNG) and liquefied petroleum gas (LPG). The stored product is also named fluid);
-   which meets specific quality requirements in order to maintain underground storage integrity, performance, environmental compatibility and fulfils contractual requirements.
This European Standard specifies common basic principles for underground gas storage facilities. Users of this European Standard should be aware that more detailed standards and/or codes of practice exist. A non-exhaustive list of relevant standards can be found in Annex A.
This European Standard is intended to be applied in association with these national standards and/or codes of practice and does not replace them.
In the event of conflicts in terms of more restrictive requirements in the national legislation/regulation with the requirements of this European Standard, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts).
NOTE   CEN/TR 13737 (all parts) contains:
-   clarification of relevant legislation/regulations applicable in a country;
-   if appropriate, more restrictive national requirements;
-   national contact point for the latest information.
This European Standard is not intended to be applied retrospectively to existing facilities.

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CEN

EN 1918-4:2016(Main)

Gas infrastructure - Underground gas storage - Part 4: Functional recommendations for storage in rock caverns

SIST EN 1918-4:2016

This European Standard covers the functional recommendations for design, construction, testing, commissioning, operation, maintenance and abandonment of underground gas storage (UGS) facilities in mined rock caverns up to and including the wellhead.
This European Standard does not cover the technology of lined rock.
NOTE 1   Even if not covered in this standard, the lined rock is an available technology.
This European Standard specifies practices which are safe and environmentally acceptable.
For necessary surface facilities for underground gas storage, EN 1918-5 applies.
In this context, "gas" is any hydrocarbon fuel:
-   which is in a gaseous state at a temperature of 15 °C and under a pressure of 0,1 MPa (this includes natural gas, compressed natural gas (CNG) and liquefied petroleum gas (LPG). The stored product is also named fluid);
-   which meets specific quality requirements in order to maintain underground storage integrity, performance, environmental compatibility and fulfils contractual requirements.
This European Standard specifies common basic principles for underground gas storage facilities. Users of this European Standard should be aware that more detailed standards and/or codes of practice exist. A non-exhaustive list of relevant standards can be found in Annex A.
This European Standard is intended to be applied in association with these national standards and/or codes of practice and does not replace them.
In the event of conflicts in terms of more restrictive requirements in the national legislation/regulation with the requirements of this European Standard, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts).
NOTE 2   CEN/TR 13737 (all parts) contains:
-   clarification of relevant legislation/regulations applicable in a country;
-   if appropriate, more restrictive national requirements;
-   national contact point for the latest information.
This European Standard is not intended to be applied retrospectively to existing facilities.

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CEN

EN 1918-3:2016(Main)

Gas infrastructure - Underground gas storage - Part 3: Functional recommendations for storage in solution-mined salt caverns

SIST EN 1918-3:2016

This European Standard covers the functional recommendations for design, construction, testing, commissioning, operation, maintenance and abandonment of underground gas storage (UGS) facilities in solution-mined salt caverns up to and including the wellhead.
It specifies practices which are safe and environmentally acceptable.
For necessary surface facilities for underground gas storage, EN 1918-5 applies.
In this context "gas" is any hydrocarbon fuel:
—   which is in a gaseous state at a temperature of 15 °C and under a pressure of 0,1 MPa (this includes natural gas, compressed natural gas (CNG) and liquefied petroleum gas (LPG). The stored product is also named fluid);
—   which meets specific quality requirements in order to maintain underground storage integrity, performance, environmental compatibility and fulfils contractual requirements.
This European Standard specifies common basic principles for underground gas storage facilities. Users of this European Standard should be aware that more detailed standards and/or codes of practice exist. A non-exhaustive list of relevant standards can be found in Annex A.
This European Standard is intended to be applied in association with these national standards and/or codes of practice and does not replace them.
In the event of conflicts in terms of more restrictive requirements in the national legislation/regulation with the requirements of this European Standard, the national legislation/regulation takes precedence as illustrated in CEN/TR 13737 (all parts).
NOTE   CEN/TR 13737 (all parts) contains:
—   clarification of relevant legislation/regulations applicable in a country;
—   if appropriate, more restrictive national requirements;
—   national contact point for the latest information.
This European Standard is not intended to be applied retrospectively to existing facilities.

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38 pages
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22-Mar-2016
29-Sep-2016
75.200
M/017
CEN/TC 234

Gas supply systems - Underground gas storage - Part 2: Functional recommendations for storage in oil and gas fields

Gasversorgungssysteme - Untertagespeicherung von Gas - Teil 2: Funktionale Empfehlungen für die Speicherung in Öl- und Gasfeldern

Système d'alimentation en gaz - Stockage souterrain de gaz - Partie 2: Recommandations fonctionnelles pour le stockage en gisements de pétrole et de gaz

Sistemi oskrbe s plinom - Podzemna plinska skladišča - 2. del: Funkcionalna priporočila za skladiščenje na naftnih in plinskih poljih

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