ANSI/ASA S3.39-1987 (R2012)

Vendor Note: This standard provides specifications for instruments designed to measure acoustic impedance, acoustic admittance, or bothquantities, within the human external ear canal. Terms that apply to these instruments and to related measurements are defined.Four types of instruments are classified. Characteristics, specifications, and recommended calibration procedures then areprovided. Material within this standard is intended both for users and for manufacturers of instruments that measure auralacoustic impedance and admittance.