ISO 18885-3:2021

Overview

ISO 18885-3:2021, "TPMS snap-in valves - Part 3: Performances", specifies test methods and minimum performance levels for TPMS snap-in tubeless valves. Published by ISO (Second edition, 2021), this part of the ISO 18885 series defines how to evaluate key functional and durability characteristics of snap-in valve assemblies used with Tire Pressure Monitoring Systems (TPMS).

Key topics and technical requirements

This standard focuses on practical test methods and conditions used to verify valve performance. Major technical topics include:

• Test conditions and fixtures
  • Requirements for representative test fixtures and rim-hole edge treatment (e.g., chamfer or radius) so results reflect real wheel conditions.
  • Installation procedures and ageing considerations (ageing profile agreed by customer and manufacturer).
• Specific test methods
  • Adhesion - cuts in the rubber cover and axial pull test (traction speed specified) to check bonding integrity.
  • Valve core seal - room, low and high temperature leak/seal verification.
  • Valve cap seal (optional) - sealing cap performance.
  • Valve-to-rim seal - low/high temperature sealing under pressure.
  • Installation tests - force to seat, pull-out and pull-back (unseating) measures.
  • Burst test - structural integrity under pressure.
  • Ozone resistance - elastomer durability to ozone exposure.
  • Flexing resistance - cyclic flexing tests and leakage criteria.
  • Corrosion test - salt spray / corrosion assessment (ISO 9227 referenced).
  • Valve core torque and cycling - torque, repetitive operation and flow rate tests.
• Acceptance/Failure criteria
  • Defined minimum performance levels and pass/fail criteria for each test (see standard for exact thresholds and measurement methods).

Applications and users

ISO 18885-3 is intended for:

• TPMS valve manufacturers - product development, validation and quality control.
• TPMS sensor and OEM wheel suppliers - component qualification and supplier audits.
• Automotive OEMs and aftermarket companies - ensuring valve durability and sealing performance.
• Testing laboratories and certification bodies - standardized test execution and reporting. Use cases include design verification, production sampling, supplier acceptance testing, and failure-analysis protocols.

Related standards

• ISO 18885-2 - TPMS snap-in valves - Part 2: Valve environment (reference for installation/indicator ring).
• ISO 9227 - Corrosion tests in artificial atmospheres - Salt spray tests (referenced for corrosion testing).
• ISO 9413 - (referenced for sealing cap examples)

Keywords: ISO 18885-3:2021, TPMS snap-in valves, tubeless valves, valve performance testing, valve-to-rim seal, flexing resistance, burst test, ozone resistance, valve core seal.