AN EVALUATION OF THE DUNBAR-KNIGHT HEARING GUARD.

Abstract

A Dunbar-Knight hearing guard was assessed with the threshold shift method using ten normal-hearing ears, and the results compared with those of the standard Navy V-51 ear plug. The attenuation provided in the frequency region 1,500 - 8,000 cycles is of the order of 20-25 db. Attenuation at 1,000 cycles and below is of the order of 10db or less, and will allow speech communications to pass unhindered. It is recommended that this hearing guard, with its lead mass which will absorb a pressure wave, be assessed at a facility which has standardized techniques for assessing the effect on hearing of impulsive noises. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 20, 1960
Accession Number
AD0639180

Entities

People

  • J. Donald Harris

Tags

DTIC Thesaurus Topics

  • Attenuation
  • Buildings And Structures
  • Frequency
  • Standards
  • Test And Evaluation

Readers

  • Acoustics.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Military Mobilization and Reserve Forces Studies.