EN 13648-1:2008

• Abstract:

  This European Standard specifies the requirements for the design, manufacture and testing of safety valves for cryogenic service, that is to say for operation with cryogenic fluids (as defined in EN 1251-1) below – 10 °C in addition to operation at ambient temperature. It is a requirement of this European Standard that the valves comply with EN ISO 4126 1 or EN ISO 4126-4. In the event of different requirements, the requirements for cryogenic service shall be applied.; NOTE 1 A cryogenic fluid (refrigerated liquefied gas) is a gas which is partially liquid because of its low temperature (including totally evaporated liquids and supercritical fluids).; This European Standard is restricted to valves not exceeding a size of DN 100 for category B. The valves of category A are limited to DN 25 and set pressures up to 40 bars. Both categories are designed to relieve single phase vapours or gases. A valve can be specified, constructed and tested such that it is suitable for use with more than one gas or with mixtures of gases.; NOTE 2 All safety valves covered in this European Standard correspond to category IV of PED (Directive 97/23/EC) and category 3 of TPED (Directive 99/36/EC).; NOTE 3 This European Standard does not provide methods for determining the capacity of relief valve(s) for a particular cryogenic vessel. Such methods are provided in EN 13648 3.

• Status: Published
• Publication Date: 18-Nov-2008
• Withdrawal Date: 30-May-2009
• ICS: 23.020.40 - Cryogenic vessels
• ICS: 23.060.40 - Pressure regulators
• Technical Committee: CEN/TC 268 - Cryogenic vessels
• Drafting Committee: CEN/TC 268/WG 2 - Compatibility, insulation, accessories
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 03-Mar-2024
• Completion Date: 02-Sep-2026
• Directive: Not Harmonized2008/68/EC - Directive 2008/68/EC of the European Parliament and of the council of 24 September 2008 on the inland transport of the dangerous goods
• Directive:

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  Harmonized Standard2014/68/EU - Directive 2014/68/EU of the European Parliament and of the Council of 15 May 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of pressure equipment
  OJ Ref: C 293/01 OJ Date: 12-Aug-2016
• Directive:

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  Not Harmonized94/55/EC - Transport of dangerous goods by road
• Directive:

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  Not Harmonized96/49/EC - Transport of dangerous goods by rail
• Directive:

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  Not Harmonized96/86/EC - Transport of dangerous goods by road (94/55/EC Dir. amendment)
• Directive:

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  Not Harmonized96/87/EC - Transport of dangerous goods by rail (96/49/EC Dir. amendment)
• Directive:

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  Not Harmonized97/23/EC - Pressure equipment
  OJ Ref: C, C 81 OJ Date: 04-Apr-2009
• Mandate: M/071 - Mandate to CEN for standardization in the field of Pressure equipment
• Mandate: M/086 - Mandate to CEN for standardization in the field of transport of dangerous goods
• Ref Project: SIST EN 13648-1:2009 - Cryogenic vessels - Safety devices for protection against excessive pressure - Part 1: Safety valves for cryogenic service

• Replaces: EN 13648-1:2002 - Cryogenic vessels - Safety devices for protection against excessive pressure - Part 1: Safety valves for cryogenic service
• Effective Date: 22-Dec-2008
• Refers: EN 1797:2001 - Cryogenic vessels - Gas/material compatibility
• Effective Date: 28-Jan-2026
• Refers: EN ISO 4126-1:2004 - Safety devices for protection against excessive pressure - Part 1: Safety valves (ISO 4126-1:2004)
• Effective Date: 28-Jan-2026
• Refers: EN ISO 21028-2:2018 - Cryogenic vessels - Toughness requirements for materials at cryogenic temperature - Part 2: Temperatures between -80 degrees C and -20 degrees C (ISO 21028-2:2018)
• Effective Date: 28-Jan-2026
• Refers: EN ISO 23208:2019 - Cryogenic vessels - Cleanliness for cryogenic service (ISO 23208:2017)
• Effective Date: 28-Jan-2026
• Refers: EN ISO 4126-4:2004 - Safety devices for protection against excessive pressure - Part 4: Pilot operated safety valves (ISO 4126-4:2004)
• Effective Date: 28-Jan-2026
• Refers: EN ISO 21028-1:2016 - Cryogenic vessels - Toughness requirements for materials at cryogenic temperature - Part 1: Temperatures below -80 °C (ISO 21028-1:2016)
• Effective Date: 28-Jan-2026
• Referred By: EN 14398-1:2003 - Cryogenic vessels - Large transportable non-vacuum insulated vessels - Part 1: Fundamental requirements
• Effective Date: 28-Jan-2026
• Referred By: EN 14197-1:2003 - Cryogenic vessels - Static non-vacuum insulated vessels - Part 1: Fundamental requirements
• Effective Date: 28-Jan-2026
• Referred By: EN 13458-2:2002 - Cryogenic vessels - Static vacuum insulated vessels - Part 2: Design, fabrication, inspection and testing
• Effective Date: 28-Jan-2026
• Referred By: EN 13530-1:2002 - Cryogenic vessels - Large transportable vacuum insulated vessels - Part 1: Fundamental requirements
• Effective Date: 28-Jan-2026

Overview - EN 13648-1:2008 (Cryogenic vessels - Safety valves for cryogenic service)

EN 13648-1:2008 is the CEN European Standard that specifies requirements for the design, manufacture and testing of safety valves for cryogenic service. It applies to valves intended to operate with cryogenic fluids (as defined in EN 1252-1) at temperatures below −10 °C as well as at ambient temperature. The standard mandates compliance with EN ISO 4126‑1 or EN ISO 4126‑4 and addresses cryogenic-specific design, material and testing considerations for reliable pressure relief.

Key topics and technical requirements

• Scope and limits
  • Valves for single‑phase vapours/gases; sizes limited to DN 100 for category B and DN 25 for category A (category A limited to set pressures up to 40 bar).
  • All covered valves correspond to PED category IV (Directive 97/23/EC) and TPED category 3 (Directive 99/36/EC).
• Design requirements
  • Suitability across specified minimum temperature up to +65 °C.
  • Measures to avoid water accumulation, freezing or deposition (drainage, stem guiding).
  • Special provisions for sublimating cryogens (e.g., CO2) to avoid solid deposition impairing operation.
• Materials
  • Metallic materials must meet toughness requirements in EN 1252‑1 / EN 1252‑2 for the specified minimum temperatures.
  • Oxygen compatibility per EN 1797 when required (e.g., oxygen service or temperatures near −190 °C).
  • Limits on copper content (e.g., with acetylene mixtures) and guidance for non‑metallic parts (seats/inserts).
• Testing
  • Production testing in accordance with EN ISO 4126‑1 / EN ISO 4126‑4 (hydraulic or pneumatic media).
  • Type tests specific to cryogenic service (seat leakage, cryogenic performance, repeated lift/reseat cycles).
  • Determination of certified derated discharge coefficient (Kdr), cleanliness and marking requirements.

Practical applications

EN 13648-1 is used to ensure safe overpressure protection of cryogenic storage and process equipment:

• Liquid and gaseous cryogenic storage tanks and transportable cryogenic vessels
• LNG/LPG facilities, industrial gas plants, research cryogenic systems
• Installations where vented fluids may freeze or sublimate on valve internals

Who uses this standard

• Pressure‑relief valve manufacturers and designers
• Cryogenic vessel manufacturers and installers
• Safety and compliance engineers, testing laboratories and notified bodies
• Procurement teams specifying valves to meet PED/TPED and CEN requirements

Related standards

• EN ISO 4126‑1 / EN ISO 4126‑4 (safety valves)
• EN 1252‑1, EN 1252‑2 (cryogenic material toughness)
• EN 1797 (gas/material compatibility)
• EN 12300 (cleanliness for cryogenic service)
• EN 13648‑3 (relief capacity, sizing)
• PED 97/23/EC and TPED 99/36/EC (regulatory context)

Keywords: EN 13648-1, cryogenic vessels, safety valves, cryogenic service, pressure relief, PED, EN ISO 4126, valve testing.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Kryo Behälter - Sicherheitseinrichtungen gegen Drucküberschreitung - Teil 1: Sicherheitsventile für den Kryo-BetriebRécipients cryogéniques - Dispositifs de protection contre les surpressions - Partie 1: Soupapes de sureté pour service cryogéniqueCryogenic vessels - Safety devices for protection against excessive pressure - Part 1: Safety valves for cryogenic service23.020.40Proti mrazu odporne posode (kriogenske posode)Cryogenic vessels13.240Varstvo pred previsokim tlakomProtection against excessive pressureICS:Ta slovenski standard je istoveten z:EN 13648-1:2008SIST EN 13648-1:2009en,fr,de01-januar-2009SIST EN 13648-1:2009SLOVENSKI
STANDARDSIST EN 13648-1:20021DGRPHãþD

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 13648-1November 2008ICS 23.020.40; 23.060.40Supersedes EN 13648-1:2002
English VersionCryogenic vessels - Safety devices for protection againstexcessive pressure - Part 1: Safety valves for cryogenic serviceRécipients cryogéniques - Dispositifs de protection contreles surpressions - Partie 1: Soupapes de sûreté pourservice cryogéniqueKryo-Behälter - Sicherheitseinrichtungen gegenDrucküberschreitung - Teil 1: Sicherheitsventile für denKryo-BetriebThis European Standard was approved by CEN on 5 October 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 13648-1:2008: ESIST EN 13648-1:2009

Standard and the Essential Requirements
of EC Directive 97/23/EC (PED).13 Bibliography.14
EN 12300, Cryogenic vessels – Cleanliness for cryogenic service EN ISO 4126-1:2004, Safety devices for protection against excessive pressure – Part 1: Safety valves (ISO 4126-1:2004) EN ISO 4126-4:2004, Safety devices for protection against excessive pressure – Part 4: Pilot operated safety valves (ISO 4126-4:2004) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 DN (nominal size) alphanumeric designation of size for components of a pipework system, which is used for reference purposes and which comprises the letters DN followed by a dimensionless whole number that is indirectly related to the physical size, in millimetres, of the bore or outside diameter of the end connections [adapted from EN ISO 6708:1995] 3.2 pressure
gauge pressure that is the value which is equal to the algebraic difference between the absolute pressure and the atmospheric pressure SIST EN 13648-1:2009

EXAMPLE A pressure regulating vent valve designed for frequent operation. 3.5 safety valve category B safety valve which would not be expected to relieve during normal operation due to the provision of an alternative relieving or control device 3.6 cryogenic fluid gas which is partially liquid because of its low temperature NOTE
The cryogenic fluids include evaporated liquids and supercritical fluids. The refrigerated but non-toxic gases given in Table 1 and mixtures of them are referred to as cryogenic fluids. SIST EN 13648-1:2009

1913 Neon, refrigerated liquid
1951 Argon, refrigerated liquid
1963 Helium, refrigerated liquid
1970 Krypton, refrigerated liquid
1977 Nitrogen , refrigerated liquid
2187 Carbon dioxide, refrigerated liquid
2591 Xenon, refrigerated liquid
3136 Trifluoromethane, refrigerated liquid
3158 Gas, refrigerated liquid, N.O.S. b 3° O Oxidizing gases
1003 Air, refrigerated liquid
1073 Oxygen, refrigerated liquid
2201 Nitrous oxide, refrigerated liquid, oxidizing
3311 Gas, refrigerated liquid, oxidizing, N.O.S b .
3° F Flammable gases
1038 Ethylene, refrigerated liquid
1961 Ethane, refrigerated liquid
1966 Hydrogen, refrigerated liquid
1972 Methane, refrigerated liquid or natural gas, refrigerated liquid, with high methane content
3138 Ethylene, acetylene and propylene mixture, refrigerated liquid, containing at least 71,5 % ethylene with not more than 22,5 % acetylene and not more than 6 % propylene
3312 Gas, refrigerated liquid, flammable, N.O.S b a
Item and group, identification number, name and description according to the United Nations. b
N.O.S. = not otherwise specified.
3.7
relieving pressure pressure used for the sizing of a safety valve which is greater than or equal to the set pressure plus overpressure
NOTE For set pressure and overpressure definitions see EN ISO 4126-1. 4 Requirements 4.1 General The valve shall satisfy all the requirements of EN ISO 4126-1 or EN ISO 4126-4 except in cases where these Standards include diverging requirements, then this European Standard shall be applied. SIST EN 13648-1:2009
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