scope:

This standard describes certain hearing aid measurements and parameters that are deemed useful in determining the electroacoustic performance of an air-conduction hearing aid. Some of these lend themselves to setting of tolerances for the purpose of maintaining product uniformity and for compliance with the performance specified for a model.

It is not the intent of this document to restrict the variety of hearing aid performance available nor to inhibit in any way advances in the state of the art.

This standard is limited to the specification of certain electroacoustic characteristics based on sinusoidal and other steady-state test signals. Measurements described in this standard are not intended to reflect in situ performance of hearing aids, directional performance of directional hearing aids, or certain performance properties of digital hearing aids, such as processing delay.

Notes in the standard are not considered to be part of the standard.

Applications

Tolerances are given relative to specified characteristics supplied by a manufacturer. In the case of "custom" or "made-to-order" hearing aids, individual test data are to be supplied. The tolerances specified in the standard will apply to the individual test data supplied.

Purpose

This standard is intended to meet the need for specifications of air-conduction hearing aid performance parameters and their tolerances. The quantities suggested for specifications and tolerances are considered to be useful for comparing performance characteristics of different hearing aids or for comparing performance characteristics of a hearing aid with published specifications.