Performance of new hearing aids using the ANSI S3.22-1976 standard

One hundred new hearing aids were tested to determine their compliance with ANSI S3.22-1976 specifications. Thirty-four models representing eight manufacturers were included. Estimates of the test equipment's accuracy were utilized as required by the standard to correct the tolerances permitted for the 11 measurements made. Results revealed that 68% of the instruments tested met all specifications, when the accuracy of the test apparatus was accounted for, while 11% fewer hearing aids passed all tests when it was excluded. No greater than a 10% difference was found in the performance of various types of aids, such as automatic gain control, directional, linear, or nondirectional.