Impulse Assessment of the Enhanced Combat Helmet - Marine Corps and the ComTac(tm) V Hearing Defender Headset
Abstract
The impulse peak insertion loss (IPIL) is the standard measure of attenuation provided by hearing protection devices (HPDs) in response to an impulsive noise. Researchers at NSMRL were interested to know the IPIL value of the Enhanced Combat Helmet - Marine Corps (ECH-M) when worn in concert with an active earmuff. This technical memorandum describes the IPIL testing conducted on the ECH-M with the ComTac V Headset in two test modes: passive (i.e., OFF) and active (i.e., MAX). Testing was done in accordance with the ANSI standard S12.42-2010. To assess the effect of donning the ECH-M on the ComTac V, one sample of the ComTac V was utilized with five samples of the ECH-M. Samples were fitted to an acoustic test fixture two times each for a total of 10 trials per test level in both the passive and active test modes. All samples were tested at the nominal levels of 160 and 170 decibel peak (dBP, re: 20 Pa). Results suggest that when properly fit and functional, the ECH-M with the ComTac V will adequately protect impulses below 167.9 dBP in the passive mode and below 168.2 dBP in the active mode.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 14, 2022
- Accession Number
- AD1156829
Entities
People
- Alexa H. Kolias
- Derek W. Schwaller
- Jeremy S. Federman
- Natalie Silvia
- Stephanie J. Karch
Organizations
- Leidos
- Naval Submarine Medical Research Laboratory