The attenuation of ear protectors was examined at 8, 10, 12, 14, 16, and 18 kHz. Four different varieties of protection devices were used. These included three types of plugs—foam, rubber, and custom fitted—and a muff. Ten young normal-hearing listeners were tested (on three different days) by means of a Békésy tracking procedure. The stimulus was a pulsed 300-Hz band of noise centered around the test frequency. The results revealed a wide range of attenuation provided by the four types of protectors. The most protection was afforded by the foam plug, followed by the rubber plug and muff. The custom mold provided the least amount of attenuation. For each protector the attenuation was relatively constant between 8 to 16 kHz, with the greatest protection offered at 14 kHz.
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