Automated lanes and biometrics
Automated passenger-hall lanes are free and use biometric verification for travellers aged six and above with suitable ICAO-compliant passports. Foreign visitors can use the lanes without prior enrolment, subject to entry requirements; first visits enrol iris, face and fingerprints. Subsequent trips with the same passport can use the enrolled iris/face. Follow prompts for fingerprints if face/iris verification fails.
Official ICA source
Written independently from ICA’s English original. The linked source supplies the complete document and subsequent updates.