ASA 125th Meeting Ottawa 1993 May

5aNS8. Real-ear attenuation provided by noise-reducing earphone enclosures.

Tom Frank

Amy C. Ritter

Dept. of Commun. Disord., Penn State Univ., 5-A Moore Bldg., University Park, PA 16802

Real-ear attenuation at threshold values were obtained for Audiocup, AudioMate, Auraldome II, and Madsen ME-70 noise-reducing earphone enclosures (N-REEs) housing a TDH-type earphone mounted in supra-aural cushion using ten subjects following the procedures specified in ANSI S12.6-1984. Overall, the attenuation provided by each N-REE increased as frequency increased and was about 8 dB from 125 to 250 Hz, 21 dB from 500 to 1000 Hz, and 35 dB from 2000 to 8000 Hz. The Audiocup provided the least (3 dB) and the AudioMate, the most (16 dB) attenuation from 125 to 250 Hz. The Auraldome II provided the least (18 dB) and the AudioMate provided the most (25 dB) attenuation from 500 to 1000 Hz. Each N-REE provided similar attenuation (35 dB) from 2000 to 8000 Hz. Compared with the attenuation values for a TDH-type earphone in a supra-aural cushion (re: ANSI S3.1-1991), each N-REE provided significantly more attenuation except for the Audiocup, Auraldome II, and Madsen ME-70 at 125 Hz and the Audiocup at 250 Hz. Implications for hearing testing using N-REEs as a means to reduce high levels of ambient noise will be discussed.