Sound attenuation performance of fiber reinforced polymer composite circumaural hearing protection devices.

Details

• Personal Author:
  Augustine SC
• Description:
  Personnel who work on the flight deck of an aircraft carrier are exposed to extreme levels of jet engine noise often in excess of 140 decibels (dB). The current circumaural hearing protective devices (CAHPD) employed by flight deck crewmen are inadequate for the level of protection required for these extreme levels of noise. Fiber-reinforced thermoset polymer composite (FRPC) materials such as aramid fibers used in body armor, have high theoretical values of acoustic impedance due to a fundamentally high modulus of elasticity and may offer a superior level of hearing protection over original equipment (OE) thermoplastic CAHPDs. The objective of this project was to measure and evaluate the attenuation of CAHPD's constructed from FRPC materials. FRPC CAHPD ear cups were paired with OE thermoplastic CAHPD ear cups of equal shape and thickness, and the protected and unprotected A-weighted sound pressure level (SPL) was measured in continuous and impulse noise environments >80 dBA using a JOLENE manikin. These data were evaluated for paired differences between the protected and unprotected mean SPL, and OE protected and FRPC protected mean SPL and indicates that OE thermoplastic CAHPDs provide greater sound attenuation of continuous noise >80 dBA and aramid FRPC CAHPDs provide greater sound attenuation of impulse noise >80 dBA. [Description provided by NIOSH]
• Subjects:
  Aircraft Glass Hearing Hearing Loss Noise Noise, Occupational Occupational Health Safety
• Keywords:
  Author Keywords: JOLENE; Impulse Noise; Continuous Noise; Fiberglass; Carbon; Aramid Sound Attenuation; Aircraft; Aircraft Engines; Aircrews; Flight Personnel; Jets; Noise Exposure; Noise Sources; Noise Protection; Hearing Loss Prevention; Hearing Protection; Acoustical Materials; Acoustic Absorption; Acoustics; Protective Materials; Protective Measures;
• Publisher:
  University of South Florida
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Thesis
• Place as Subject:
  Florida ; OSHA Region 4
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-48
• NIOSHTIC Number:
  nn:20065731
• Citation:
  Tampa, FL: University of South Florida, 2015 Jan; :1-48
• Email:
  steveaugustine01@hotmail.com
• CAS Registry Number:
  Carbon (CAS RN 7440-44-0) ; p-Phenylenediamine-terephthalic acid copolymer, SRU
• Federal Fiscal Year:
  2015
• Performing Organization:
  Sunshine Education and Research Center, University of South Florida
• Peer Reviewed:
  False
• Start Date:
  20050701
• Source Full Name:
  Sound attenuation performance of fiber reinforced polymer composite circumaural hearing protection devices
• End Date:
  20290630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:4c9f6c4ebd1f3dc2f5b0fb83df3f5f522d3cfba8c85e3ebd29a7c802e19ac577dd0a7f3fc84b51ff2361b7ae2c46df0bfdc79cfae9b6a73c8596fa4c076e46f7
• Download URL:
  https://stacks.cdc.gov/view/cdc/249531/cdc_249531_DS1.pdf
• File Type:
  [PDF - 2.86 MB ]