This standard BS ISO 2026:2020 Aircraft. Connections for starting engines by air is classified in these ICS categories:
49.100 Ground service and maintenance equipment
49.080 Aerospace fluid systems and components
This document specifies the dimensions of connections for starting aircraft engines by air, which are necessary to ensure international interchangeability of connectors with adaptors. lt also gives the minimum clearances required on the aircraft to provide adequate access for the ground adaptor.