What is BS EN 1918-4 - Functional recommendations for gas storage in rock caverns about?
BS EN 1918-4 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.
BS EN 1918-4 specifies practices which are safe and environmentally acceptable.
BS EN 1918-4 specifies common basic principles for underground gas storage facilities.
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.
Note 1: Users of BS EN 1918-4 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.
Note 2: BS EN 1918-4 is not intended to be applied retrospectively to existing facilities.
Note 3: BS EN 1918-4 does not cover the technology of lined rock.
Note 4: For necessary surface facilities for underground gas storage, EN 1918-5 applies.
Who is BS EN 1918-4 - Functional recommendations for gas storage in rock caverns for?
BS EN 1918-4 – on functional recommendations for gas storage in rock caverns is useful for:
- Petroleum and natural gas industry
- UGS plants
- Installation and operation units of rock caverns
- Environmental safety agencies
- Disaster management departments
Why should you use BS EN 1918-4 - Functional recommendations for gas storage in rock caverns?
Underground gas storage (UGS) is an efficient proven common technology and is in use since 1915. UGS became an essential indispensable link in the gas supply chain for adjusting supply to meet short-term and seasonal changes in demand.
The primary function of UGS is to ensure that supply is adjusted for peak and seasonal demand. Apart from this, the storage facilities can provide stand-by reserves in case of interruption of the planned supply. Increasingly UGS is applied for commercial storage services.
Underground storage in mined caverns as specified in BS EN 1918-4 is an alternative to underground storage in salt leached caverns, especially where the local geological conditions do not provide salt or where the salt does not offer suitable characteristics for solution mining.
Generally spoken, a mined cavern storage facility comprises subsurface facilities of access works by tunnel or/and shaft, one or several galleries, excavated in hard rock, operation shaft and related surface facilities for handling of the stored product.
Unlined mined cavern technology is widely used in the field of underground storage for:
- Liquids (crude oil, distillates, etc.)
- Liquefied petroleum gas (LPG)
BS EN 1918-4 specifies underground storage in mined caverns, which is a safe way to create reserves of oil and gas products in the immediate vicinity of producing, importing, or consuming centres such as:
- Refineries, import or export terminals
- Petrochemical complexes for which LPG constitutes a feedstock
- Local storage for seasonal peak shaving
What’s changed since the last update?
BS EN 1918-4:2016 supersedes EN 1918-4:1998. BS EN 1918-4:2016 includes some technical changes with respect to BS EN 1918-4:2016. These include:
- More details on function and technology of underground storage, including figures
- Addition of activities and reviews related to safety
- Addition of HSE chapter
- Addition of Abandonment chapter

