KS I ISO 389-2:2014 Acoustics — Reference zero for the calibration of audiometric equipment — Part 2: Reference equivalent threshold sound pressure levels for pure tones and insert earphones
2020KS I ISO 389-2:2020 Acoustics — Reference zero for the calibration of audiometric equipment — Part 2: Reference equivalent threshold sound pressure Ievels for pure tones and insert earphones
2014KS I ISO 389-2:2014 Acoustics — Reference zero for the calibration of audiometric equipment — Part 2: Reference equivalent threshold sound pressure levels for pure tones and insert earphones
2003KS I ISO 389-2:2003 Acoustics-Reference zero for the calibration of audiometric equipment-Part 2:Reference equivalent threshold sound pressure levelsfor pure tones and insert earphones