Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and insert earphones Ingestion-build-47182 This part of ISO 14837

This part of ISO 14837 does not deal with vibration arising from the construction and maintenance of the rail system

general purpose (code B)

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This method corresponds to a phase 2

Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and insert earphones Ingestion-build-47182 This part of ISO 148371 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