ISO 16992:2018

Overview

ISO 16992:2018 - "Passenger car tyres - Spare unit substitutive equipment (SUSE)" defines performance and qualification criteria for equipment intended to substitute a spare wheel/tire and permit continued vehicle mobility after a loss of tyre functional efficiency. The standard covers systems that enable “extended mobility” (ability to continue driving after a tyre failure) and specifies the behaviour, endurance testing and marking requirements for SUSE systems from the moment they become effective. Key concepts include run-flat tyres, extended mobility tyres (EMT), internal support rings, and the requirement for a run-flat warning system (RFWS).

Key topics and technical requirements

• Scope and intent: Qualifies SUSE systems that permit extended mobility; does not cover the vehicle design, tyre performance in normal inflated mode, or servicing after activation.
• Types of SUSE:
  • Run-flat/self-supporting tyres (SST)
  • Extended mobility tyres (EMT)
  • Tyres with internal support rings
• Performance baseline: SUSE systems shall allow controlled flat-tyre running at 80 km/h for 80 km (from the moment the system becomes effective), with the driver retaining control of speed and direction.
• Activation and warning: SUSE systems must activate automatically in the event of loss of tyre functional efficiency and include an RFWS to inform the driver that flat-tyre running mode has been reached and to report failures of the warning function.
• Endurance testing: The standard defines endurance tests for different SUSE types (run-flat/self-supporting/internal ring and extended mobility tyres) to verify capability under flat-tyre running conditions.
• Conformance: While in inflated mode, tyres that are part of a SUSE must conform to usual tyre standards (e.g., ISO 4000 and ISO 10191) and not degrade normal service properties.
• Markings and symbols: ISO 16992 specifies pictograms and sidewall markings (for run-flat, extended mobility and internal support ring identification) to communicate SUSE capability.

Applications and who uses it

• Tyre manufacturers - product development, compliance testing and marking for run-flat and EMT products.
• Vehicle manufacturers (OEMs) - specifying acceptable SUSE systems for fitment and integration with vehicle warning systems.
• Testing and certification labs - performing endurance and conformance tests per ISO 16992.
• Regulatory bodies & accreditation - defining safety and labeling requirements for market access.
• Fleet operators & aftermarket suppliers - selecting SUSE solutions (run-flat, EMT or support rings) to improve uptime and roadside safety.

Related standards

• ISO 4000 (Passenger car tyres and rims)
• ISO 10191 (Verifying tyre capabilities - laboratory test methods)
• ISO symbols referenced (ISO 7000 series for pictograms)

Keywords: ISO 16992:2018, SUSE, spare unit substitutive equipment, run-flat tyre, extended mobility tyre, RFWS, endurance test, tyre marking, ISO tyre standards.