ISO 15500-18:2020

Overview

ISO 15500-18:2020 is an international standard specifying the requirements and test methods for filters used in compressed natural gas (CNG) fuel systems for road vehicles. It covers filter components designed for mono-fuel, bi-fuel, or dual-fuel CNG vehicles as defined under ISO 3833 and utilizing natural gas quality in accordance with the ISO 15403 series. This standard ensures that CNG filters meet essential safety, durability, and performance criteria necessary for reliable operation in automotive fuel systems.

Key exclusions from this standard include liquefied natural gas (LNG) components upstream of vaporizers, fuel containers, stationary gas engines, container-mounting hardware, electronic fuel management systems, and refuelling receptacles.

Key Topics

• Scope and Applicability:
  The standard applies specifically to CNG fuel system filters for road vehicles using natural gas fuel, excluding LNG components and other fuel system parts not directly related to filters.

• Marking and Traceability:
  Filters must be clearly marked to provide manufacturer identification, model designation, working pressure and temperature range, flow direction, and serial numbers or date codes. Additional markings may include certification symbols, type approval numbers, and references to ISO 15500-18:2020.

• Construction and Assembly Requirements:
  The filters must comply with general construction and performance requirements outlined in ISO 15500-1 and ISO 15500-2. Special considerations apply to the use of non-conductive materials, requiring design adjustments to ensure safety and conductivity where needed.

• Testing Procedures:
  The standard mandates rigorous testing such as:

  • Hydrostatic strength tests at 2.5 times the nominal working pressure to verify mechanical integrity.
  • Continued operation testing for 20,000 cycles to simulate long-term use, followed by hydrostatic strength verification.
  • Additional tests referenced from ISO 15500-2 including leakage, torque resistance, bending moment, corrosion resistance, ageing tests (oxygen, ozone, heat), automotive fluid exposure, vibration resistance, brass compatibility, and others.

Applications

ISO 15500-18:2020 is critical for manufacturers and suppliers involved in producing CNG fuel filters for road vehicles. The standard supports:

• Ensuring fuel system safety by certifying filter durability under high pressure and cyclic operation.
• Enhancing fuel system reliability by requiring filters that prevent contaminants from entering sensitive components of CNG engines.
• Facilitating regulatory compliance across global markets where adherence to ISO standards is expected or mandated.
• Supporting vehicle manufacturers with standardized components that fit varied CNG vehicle platforms (mono-fuel, bi-fuel, dual-fuel).

This standard is especially relevant for automotive component designers, testing laboratories, certification agencies, and regulatory bodies engaged in natural gas fuel system safety and performance validation.

Related Standards

• ISO 15500-1:2020 – General requirements and definitions for CNG fuel system components.
• ISO 15500-2:2020 – Performance and general test methods for CNG system components, providing essential testing procedures referenced in Part 18.
• ISO 3833 – Classification and terminology of road vehicle types, defining the vehicle categories targeted by this standard.
• ISO 15403 series – Specifications for natural gas quality used as fuel in CNG vehicles, ensuring fuel compatibility with filtering systems.

By aligning with these interconnected ISO standards, ISO 15500-18:2020 ensures comprehensive coverage of compressed natural gas fuel system safety, reliability, and performance. This facilitates the global adoption of cleaner fuel technologies with confidence in component functionality and safety.

Keywords: ISO 15500-18:2020, CNG fuel filter standard, compressed natural gas filter requirements, road vehicles CNG components, CNG fuel system testing, natural gas vehicle safety, ISO CNG standards, fuel system filter performance, automotive CNG filters compliance.