SN EN 60645-1 : 1994

Introduction
1 Scope and object
2 Normative references
3 Terms and Definitions
4 Requirements for specific types of fixed frequency
   audiometer
5 General requirements
   5.1 Electrical safety requirements
   5.2 Acoustic safety requirements
   5.3 Environmental conditions
   5.4 Warm-up time
   5.5 Power supply variation
        5.5.1 Mains operation
        5.5.2 Battery operation
   5.6 Immunity to power and radio frequency fields
   5.7 Unwanted sound
        5.7.1 General
        5.7.2 Unwanted sound from an earphone
        5.7.3 Unwanted sound radiated by an audiometer
   5.8 Testing of automatic recording and
        computer-controlled audiometers
   5.9 Interface connections
6 Test signal sources
   6.1 Pure tones
        6.1.1 Frequency range and hearing level range
        6.1.2 Frequency accuracy
        6.1.3 Total harmonic distortion
        6.1.4 Rate of frequency change
   6.2 Frequency modulation
   6.3 External signal source
        6.3.1 Signals
        6.3.2 Frequency response
        6.3.3 Electrical sensitivity
        6.3.4 Reference level for external signal source
        6.3.5 Operator to subject speech communication
        6.3.6 Subject to operator speech communication
   6.4 Masking sounds
        6.4.1 General
        6.4.2 Narrow-band noise
        6.4.3 Other masking sound
7 Loudspeaker output
8 Signal level control
   8.1 Marking
   8.2 Signal indicator
   8.3 Accuracy of sound pressure level and vibratory
        force level
   8.4 Hearing level control
        8.4.1 Manual audiometers
        8.4.2 Automatic-recording audiometers
        8.4.3 Computer-controlled audiometers
        8.4.4 Accuracy of control
   8.5 Masking level sound
        8.5.1 General
        8.5.2 Masking level
        8.5.3 Accuracy of masking levels
        8.5.4 Masking level range
   8.6 Tone switching
        8.6.1 Tone switch for manual audiometers
        8.6.2 On/off ratio for manual audiometers
        8.6.3 Rise/fall times for manual audiometers
        8.6.4 Automatic pulsed presentation
        8.6.5 Subject's response time with
               computer-controlled audiometers
9 Reference tone
   9.1 General
   9.2 Frequencies
   9.3 Reference tone level control
        9.3.1 Range
        9.3.2 Intervals
        9.3.3 Marking
        9.3.4 Accuracy
        9.3.5 Operation
10 Calibration
   10.1 General
   10.2 Supra-aural earphone headband
   10.3 Bone vibrator headband
11 Electrical output
12 Audiogram format
13 Demonstration of conformity with specifications and
   test procedures
   13.1 General
   13.2 Environmental conditions and power supply
        variation
   13.3 Immunity to power and radio frequency fields
   13.4 Unwanted sound
        13.4.1 Earphone
        13.4.2 Unwanted sound from a bone vibrator
        13.4.3 Unwanted sound radiated by an audiometer
   13.5 Test signal sources
   13.6 Signal accuracy
        13.6.1 Accuracy of sound pressure level and
               vibratory force
        13.6.2 Accuracy of control
   13.7 Masking sound
        13.7.1 Narrow-band noise
        13.7.2 Masking level
   13.8 Headbands
        13.8.1 Supra-aural earphone headband
        13.8.2 Bone vibrator headband
14 Maximum permitted expanded uncertainty of measurements
15 Marking and instruction manual
     15.1 Marking
     15.2 Instruction manual
Bibliography
Annex ZA (normative) Normative references to international
         publications with their corresponding European
         publications

Specifies particular requirements for pure-tone audiometers designed for use in determining hearing threshold levels in comparison with the standard reference threshold levels by means of psycho-acoustic test methods. Coverage includes: safety requirements, warm-up time, pure tones, marking, masking sound, bone conduction, and hearing level control. Also gives detailed definitions and tables.