Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and insert earphones Ingestion-build-47182 The required levels are to

The required levels are to be found in local regulations or non-conflicting standards

general purpose (code B)

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The testing of pure FAME (which is in the scope of EN ISO 5165) has been excluded from the scope for the time being as there seem to be sample-specific biases for such product

Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and insert earphones Ingestion-build-47182 The required levels are to1 Scope This part of ISO 389 specifies reference equivalent threshold sound pressure levels (RETSPL) for the calibration of pure tone audiometers supplementary to those specified in ISO 389: 19911). Values given in this part of ISO 389 are applicable to insert earphones of a pattern specified in clause 4. NOTE 1 For information, a note on the derivation of the reference values and the origin of the data input is given in annex A, and a bibliography is