End user specifications are not static. They evolve in response to updated international standards, lessons learned in the field, and – increasingly – health, safety, and emissions requirements driven by net zero commitments.
The valve that met your specification yesterday may not meet it today. For manufacturers, that means going back to the drawing board: a redesign, and a full re-qualification to the latest standard, reviewed, witnessed, and certified by an independent third party.
Here are the key areas to consider.
Fugitive emissions
ISO 15848 Part 1 (2015, amended 2017) sets the testing procedure for external leakage from valve stem seals and body joints on isolating and control valves used with volatile air pollutants and hazardous fluids. Its purpose is to classify valve performance in reducing fugitive emissions – which can pose safety, environmental, and production risks.
Low emissions performance is classified as AH, BH, or CH. In oil and gas, BH is typically specified for PTFE or elastomeric seals; AH is required for lethal applications such as H2S service, where bellow-sealed valves apply. Endurance class is also significant: the minimum for isolation valves is 205 mechanical cycles across two thermal cycles (classified as C01). The 2006 revision of this standard has been withdrawn – any certification referencing it is no longer valid. ISO 15848 is also referenced in API-6D Annex M for hydrogen applications.
Fire testing
ISO 10497:2022 covers fire type testing for soft and metal seated valves, updating the 2010 revision. Key changes include monitoring of cavity pressure relief for double-seated valves and updated materials of construction – meaning, for instance, that an F44/6Mo valve must now be fire tested in its actual material of construction rather than covered by a similar material. If a design changes fundamentally, re-testing to the latest standard is required. Certificates should always be verified and witnessed by an independent third party with a demonstrable track record.
Low temperature testing
EEMUA 192 (2015) covers low temperature testing between 0 and -50°C for moderately cold service conditions. The purpose is to confirm valve operability and sealing performance at low temperatures under pressure, replicating real operational conditions. Some manufacturers will state non-operational at -50°C, operational to -29°C – which is not acceptable when your application may require operation at the lower limit. Testing must be conducted on the valve as a complete unit, not on individual components. Elastomeric manufacturers may quote a minimum temperature, but that figure applies in a static state, without pressure or rotation. Working with an elastomeric supplier who can provide case studies in comparable applications is advisable.
Operator specifications
End user specifications go beyond qualification testing standards. They are written around the operator’s specific requirements and incorporate lessons learned at asset level. For example, EEMUA 182 provides the basis for DBB valve specifications, but operators typically add clauses from their own operational experience – such as requirements for inboard primary seals and outboard secondary seals on unwelded threaded plugs to prevent thread degradation and corrosion.
What to check
Some manufacturers overlook the re-qualification process entirely, supplying valves with documentation that no longer covers the specified design. A fire test certificate for a single sealing stem does not cover a double sealing stem. An emissions certificate to a withdrawn standard revision is not valid.
Our recommendation: always review the full test report, not just the certificate. A certificate summarises; a report tells you the whole story. Check pressures, temperature ranges, endurance class, emissions classification, materials, sealing configuration, and the revision dates of the standards referenced. Ensure the qualified design matches what you are specifying.
Where possible, engage directly with the manufacturer at a technical level. Relying on multiple layers of the supply chain introduces the risk of distortion between original specification and final supply.
Colson Valves designs and qualifies valves in-house at our facility in Rotherham. If you need a valve specified and qualified to current standards, contact the team.