Joint Service Aircrew Mask (JSAM) - Tactical Aircraft (TA) A/P22P-14A Respirator Assembly (V)3: Noise Attenuation and Speech Intelligibility Performance with Double Hearing Protection, HGU-68/P Flight Helmet
Abstract
Noise attenuation and speech intelligibility measurements were conducted in accordance with American National Standards Institute (ANSI) S12.6-1997 Methods for Measuring the Real-Ear Attenuation of Hearing Protectors and ANSI S3.2-2009Method for Measuring the Intelligibility of Speech over Communication Systems on the Joint Service Aircrew MaskTactical Aircraft (JSAM-TA) A/P22P-14A Respirator Assembly (V)3 with the HGU-68/P flight helmet in combination with Communications Earplug (CEP) and 3M EAR Classic foam earplugs. The objective of these measurements was to determine if the JSAM-TA performance requirements were met when double hearing protection was used. The addition of the JSAM-TA Respirator Assembly (V)3 to both helmet/earplug configurations, HGU-68/P with CEP and HGU-68/P with EAR Classic, met noise attenuation requirements across all frequencies, ranging from 125 to 8000 hertz (Hz). Additionally, JSAM-TA configurations with the HGU-68/P and both CEP and EAR Classic met the speech intelligibility requirement ( 80%) for low-noise environments, when using a torso-mounted Intercommunications Unit (ICU), with scores of 85.3% and 83.0%, respectively. In high-noise environments, when hardwired into an aircraft communication system, speech intelligibility requirements with CEP configurations were met with a score of 85.4% at 115 decibels dB. High-noise speech intelligibility requirements were not met for the EAR Classic configuration, with a score of 76.7% at 95 dB.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 31, 2017
- Accession Number
- AD1034182
Entities
People
- Billy Swayne
- Hilary Gallagher
Organizations
- 711th Human Performance Wing