FLIGHT DECK NOISE-EXCLUSION PERSONNEL HELMET (FDPH) EVALUATION

Abstract

Eight FDP helmets were tested for noise reducing qualities by means of a calibrated condenser microphone placed within a plaster dummy head to simulate the human ear. The attenuation characteristics for each helmet were determined over the audible spectrum at each of 11 discrete frequencies. Two types of sounds were used for the over-all noise level measurements: (1) 124 db of recorded JRB, twin-engine noise and (2) 124 db of American Standard Association white noise. The helmets were not effective in attenuating noise frequencies below 500 cps; the helmet with the greatest mass was the most effective. Occluding the ear canal by a standard ear warden appeared to offer greater protection than any of the helmets.

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Document Details

Document Type
Technical Report
Publication Date
May 07, 1953
Accession Number
AD0019388

Entities

People

  • Gilbert C. Tolhurst
  • Scott N. Morrill

Organizations

  • Ohio State University

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Ambient Noise
  • Aviation Medicine
  • Coverings
  • Ear
  • Earphones
  • Flight Decks
  • Frequency
  • Frequency Response
  • Generators
  • Government Procurement
  • Measurement
  • Microphones
  • Navy
  • Noise
  • Protective Coverings
  • Standards
  • White Noise

Readers

  • Acoustics.
  • Military Engineering.
  • Trauma Surgery or Emergency Medicine.