ISO 5208:2015

Overview

ISO 5208:2015 - Industrial valves - Pressure testing of metallic valves establishes standardized examinations and pressure-test procedures manufacturers must follow to verify the integrity of the pressure boundary, the tightness of valve closures, and the structural adequacy of closure mechanisms for metallic industrial valves. Published as the fourth edition in 2015, the standard is intended to be applied together with valve product standards; where a product standard conflicts, the product standard prevails. ISO 5208:2015 does not address the safety aspects of pressure testing - users must manage test safety and national regulatory compliance.

Key topics and technical requirements

• Scope and purpose: Defines requirements for validating shell strength and closure leakage performance of metallic valves used in general industry, power generation, petroleum and petrochemical applications.
• Test types:
  • Closure test - verifies leakage through the valve’s closure mechanism.
  • Shell test - pressure test above the valve’s cold working pressure (CWP) to validate pressure-containing structures.
  • Optional backseat test - where applicable, to check leakage at the backseat area.
• Test fluid and temperature: Test fluid may be liquid or gas; test fluid temperature is specified as > 5 °C and ≤ 40 °C.
• Test pressures and durations: Shell tests are at pressures in excess of CWP; closure and backseat test pressures and durations are specified per test type and product standard references.
• Acceptance criteria: Includes visually detectable leakage definition and quantitative acceptance rules for closure and shell tests.
• Test equipment and measurement:
  • Test equipment must not apply external loads that alter test results (e.g., excessive end-clamping).
  • Pressure measuring equipment accuracy: ±5% of the required test pressure.
  • Manufacturers must demonstrate equivalence for volume-loss or other detection systems.
• Purchaser options and witnessing: Purchasers can specify tests to be witnessed; manufacturers must provide notice and access per the standard.
• Certification: Requirements for documentation/certification of compliance after testing.

Practical applications and users

ISO 5208:2015 is used by:

• Valve manufacturers - to establish QA/test procedures and certify products.
• Test facilities - to design compliant test rigs and protocols.
• Procurement/specification engineers - to define acceptance and witnessing requirements in purchase orders.
• Plant operators and inspectors - to interpret valve test reports for piping systems in power, petroleum, petrochemical and general industry. Keywords: ISO 5208:2015, pressure testing, metallic valves, closure test, shell test, test fluid, cold working pressure, valve certification.

Related standards

• EN 12266 (valve testing practices referenced)
• API 598 (valve inspection and testing referenced)
• ISO/TC 153 (technical committee for valves)

Use ISO 5208:2015 together with applicable valve product standards to ensure full conformity with product-specific requirements.