KS I ISO 389-1:2014 Acoustics — Reference zero for the calibration of audiometric equipment — Part 1: Reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones
2020KS I ISO 389-1:2020 Acoustics — Reference zero for the calibration of audiometric equipment — Part 1: Reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones
2014KS I ISO 389-1:2014 Acoustics — Reference zero for the calibration of audiometric equipment — Part 1: Reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones
2003KS I ISO 389-1:2003 Acoustics-Reference zero for the calibration of audiometric equipment-Part 1:Reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones