ISO 2434:1973

Overview

ISO 2434:1973 is an international standard developed by the International Organization for Standardization (ISO) that specifies the requirements for compressed non-breathing air used in aircraft. This standard defines the pressure levels and quality characteristics of air compressed using oil-lubricated equipment specifically for aircraft system applications. It is important to note that ISO 2434:1973 does not cover air intended for breathing purposes or for use in oxygen systems. Instead, the focus is on ensuring that non-breathing compressed air used in aircraft meets stringent purity and pressure requirements to maintain safety and system integrity.

Key Topics

• Pressure Requirements
  The standard mandates that the compressed air supply pressure must be adequate to charge aircraft systems up to 343 bar (approximately 4,975 psi) at 20 °C. This ensures compatibility with high-pressure aircraft pneumatic systems currently utilized in aerospace engineering.

• Purity and Contaminant Limits
  To protect aircraft components, the air must contain no more than 0.005 mg of oil vapor and particulate matter per liter (cubic decimeter) of air, measured at 15 °C and 1013 mbar atmospheric pressure. This low oil vapor content limits contamination and potential damage to pneumatic systems.

• Water Content
  The water content in the compressed air must not exceed 0.02 mg per liter at the same standard conditions (15 °C and 1013 mbar). Controlling moisture is critical to preventing corrosion or ice formation in high-altitude flight conditions.

• Particulate Filtration
  Any particulate matter must be filterable, passing through a filter with a nominal rating of 10 microns. This requirement helps maintain air purity and equipment protection by preventing abrasive particles from entering sensitive aircraft systems.

Applications

ISO 2434:1973 is primarily applied in:

• Aircraft Pneumatic Systems
  Ensuring the compressed non-breathing air used for system actuation and control meets required pressure and purity standards, which is vital for hydraulic, pneumatic, and auxiliary power units.

• Aircraft Maintenance and Manufacturing
  Guiding manufacturers and maintenance providers on the specifications for compressed air to ensure reliability and safety of aircraft pneumatic equipment.

• Aerospace Engineering
  Supporting design and testing processes to comply with international standards when implementing compressed air systems not intended for breathing or oxygen-enriched environments.

By adhering to ISO 2434, aerospace industries can uphold quality and safety standards critical to modern aviation operations.

Related Standards

• ISO/TC 20 – Aircraft and Space Vehicles
  The technical committee responsible for the development of ISO 2434 and related aerospace standards.

• Standards for Breathing Air
  Refer to other ISO standards covering compressed air for breathing and oxygen systems, which are excluded under ISO 2434.

• Pressure Vessel and Pneumatic Components Standards
  Applicable for the design and testing of pressure vessels and pneumatic devices that interact with compressed air specified by ISO 2434.

Keywords: ISO 2434, compressed air for aircraft, non-breathing air, aircraft pneumatic systems, compressed air pressure, oil vapor limits, particulate filtration, aerospace standards, aircraft maintenance, aviation compressed air quality.