ISO 10497 Valve Fire Test: Procedure, Acceptance Criteria and Certificate

ISO 10497 is the international standard for fire type-testing of valves. It is the reference most often named in projects written to ISO rather than API, and it is frequently used alongside API 607 or API 6FA so one valve model can be sold into both markets. This article walks through how the test is actually run.

Scope

ISO 10497 specifies fire type-test requirements and the qualification method for valves intended for flammable service. It defines the burn environment, the test sequence, the leakage measurements and the rules for extending a qualification across a product family.

Test procedure step by step

1. Preparation. The valve is installed in the test rig in its normal operating orientation, filled with water and pressurised to the specified test pressure.
2. Baseline measurement. Leakage is measured at ambient conditions before the burn so post-fire performance has a reference point.
3. Burn exposure. The valve is engulfed in a flame maintained within the standard's temperature band, typically for 30 minutes, with thermocouples verifying the exposure.
4. Leakage during the burn. Through-seat leakage and external leakage are measured while the valve is at temperature.
5. Operational test. The valve is cycled during or immediately after the burn to prove it can still be operated to isolate the line.
6. Cool-down. The valve is cooled, by the method specified for the test, to ambient.
7. Post-cooling seat test. Low-pressure and, where required, high-pressure seat tests are repeated and leakage measured again.

Acceptance criteria

A valve passes when, within the defined measurement intervals:

• Through-seat leakage stays within the maximum permitted rate for the valve size and pressure class
• External leakage — from body joints, stem packing and the body-to-bonnet joint — stays within the permitted rate
• Operability is demonstrated: the valve can be cycled as required by the standard during and after the fire exposure

The exact numeric limits and measurement intervals are set by the standard and by the edition referenced in the contract; they differ from the limits in API 607 and API 6FA, which is why a certificate must always name the standard and edition it was tested against.

What the certificate contains

• Valve identification: type, model, size, pressure class, serial number
• Materials of construction relevant to sealing (body, seat, stem packing, gaskets)
• The standard and edition tested against
• Burn duration, temperature range and cooling method
• Measured leakage values against the permitted limits
• Operability result
• The qualification range covered, where applicable
• Testing body identification, report number and date

ISO 10497 vs API 607 and API 6FA

ISO 10497 is the general international method. API 607 is specific to quarter-turn and soft-seated valves; API 6FA covers pipeline valves and wellhead equipment. A valve sold internationally is often qualified to ISO 10497 plus whichever API standard the target market expects. Testing to the wrong one produces a certificate the purchaser will reject.

How Valverz can help

Valverz is a third-party testing body conducting ISO 10497 valve fire tests and issuing independent reports and certificates. Send your valve specification and target standard for a test plan and quotation within 1 working day. Contact: +86-18731031297 (WeChat available).