Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and circumaural earphones Ingestion-build-63114 Pressurized enclosures where the containment

Pressurized enclosures where the containment system may release air with an oxygen content greater than normal

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Second-party verification (e

System selection: The prescriptive approach

0 % (m/m)

Acoustics. Reference zero for the calibration of audiometric equipment - Reference equivalent threshold sound pressure levels for pure tones and circumaural earphones Ingestion-build-63114 Pressurized enclosures where the containment1 Scope This part of ISO 389 specifies reference equivalent threshold sound pressure levels (RETSPLs) for pure tones in the frequency range from 125 Hz to 8 kHz, applicable to the calibration of air conduction audiometers equipped with a particular model of circumaural earphones (SENNHEISER HDA 200). NOTE Some notes and references on the derivation and the test conditions used to determine the recommended reference levels are given in Annex A and the