These specifications for methods of measurement of hearing aids were drawn up by a technical committee organized by the American Hearing Aid Association, including engineering representatives from most of the larger manufacturers of hearing aids as well as technical representatives from non‐commercial groups who have been working in this field. It is believed that these specifications represent the best of present practice, although additions may be made later to cover further material such as methods of applying correction factors for the baffle effect of the body of the wearer, for the difference between the pressure and the free field characteristics of the ear, and for possible leakage of sound between the ear and the ear insert, as well as standardized methods of measurement of instruments with bone conduction receivers and of carbon type hearing aids. Since sufficient information is not yet available to reach definite conclusions on these points, the code is offered in its present form for consideration by those interested in this subject.