NF S30-001-1:2000 Acoustics - Reference zero for the calibration of audiometric equipment - Part 1 : reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones.
2000NF S30-001-1:2000 Acoustics - Reference zero for the calibration of audiometric equipment - Part 1 : reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones.