IS 6229 : 1980 Method for Measurement of Real-ear Protection of Hearing Protectors and Physical Attenuation of Earmuffs

1 Scope

1.1 This standard specifies the psychophysical procedures,physical requirements, and means of reporting results for measuringthe protective and attenuation characteristics of wearable devicesthat are used to protect the auditory system against excessivesound.

1.2 Real-Ear Protection Method - Procedures described in thereal-ear (primary) method are performed by psychoacoustic tests onhuman subjects and are designed to measure real-ear protection athearing threshold for completely developed hearing protectors. Thisprimary method is described in 3.

1.3 Physical Attenuation Method - Procedures described in thephysical attenuation (supplemental) method are performed byphysical tests on a dummy head and also may be used to measuresound attenuation at relatively high sound pressure levels. Thesupplemental method applies to earmuff-type devices and providesdata for use in earmuff design and production quality control, aswell as for various other attenuation performance specificationpurposes.

Note - A real-head physical attenuation method (that is,microphone under an earcup worn by subject), as has sometimes beenapplied in research and development work, is not standardized inthis document. Data and experience with this method have beenexamined and found to be insufficient for development of a uniformprocedure suitable for standardization at this time.

2 References

IS 2 :1960 Rules for rounding offnumerical values

IS 9098 : 1979Specification for pure tone audiometers