DIN EN 24869-3:1994 Acoustics; hearing protectors; Part 3: Simplified method for the measurement of insertion loss of ear-muff type protectors for quality inspection purposes
2007DIN EN ISO 4869-3:2007 Acoustics - Hearing protectors - Part 3: Measurement of insertion loss of ear-muff type protectors using an acoustic test fixture (ISO 4869-3:2007); English version of DIN EN ISO 4869-3:2007-09
1994DIN EN 24869-3:1994 Acoustics; hearing protectors; Part 3: Simplified method for the measurement of insertion loss of ear-muff type protectors for quality inspection purposes