BS EN 60118-8:2005

INTRODUCTION
1 Scope
2 Normative references
3 Terms and definitions
4 Limitations
5 Test equipment
  5.1 Acoustical requirements for the test space
  5.2 Sound source
  5.3 Manikin
  5.4 Ear simulator
  5.5 Ear insert simulator
  5.6 Equipment for the measurement of occluded-ear simulator
      sound pressure level
  5.7 Equipment for automatic sweep frequency recording
  5.8 Equipment for calibration of free field sound pressure level
6 Test conditions
  6.1 Choice of test point
  6.2 Ambient conditions
  6.3 Manikin
  6.4 Location of the hearing aid
  6.5 Normal operating conditions for the hearing aid
7 Measurements
  7.1 General
  7.2 Adjustment of the reference input sound pressure level
  7.3 Manikin frequency response (MFR)
  7.4 Full-on simulated insertion gain measured by the constant
      reference input SPL method
  7.5 Full-on simulated insertion gain measured by the constant
      ear simulator SPL method
  7.6 Directional characteristics
  7.7 Simulated in situ OSPL measurements
  7.8 Simplified method to measure simulated in situ and
      insertion gain response
8 Frequency response recording charts
9 Maximum permitted expanded uncertainty of measurements
Annex A (normative) Free-field to hearing-aid-microphone
        transformation
Annex B (normative) Manikin unoccluded-ear gain (open ear
        response)
Annex C (informative) General requirements for a manikin
Annex ZA (normative) Normative references to international
         publications with their corresponding European
         publications
Bibliography

Specifies methods for a test which simulates the acoustical effects of a median adult wearer on the performance of a hearing aid.

Describes methods for a test which simulates the acoustical effects of a median adult wearer on the performance of a hearing aid. Establishes certain guidelines for simulated in situ measurements of hearing aids; it describes a simplified method for simulated in situ measurements of hearing aids and a description for determination of the directivity index (DI) of directional microphones in hearing aids in the horizontal plane. In addition this second edition now specifies tolerances. Conformance to the specifications in this International Standard is demonstrated only when the result of a measurement, extended by the actual expanded uncertainty of measurement of the testing laboratory, lies fully within the tolerances specified in this International Standard extended by the values for Umax