Accession Number:

AD1175391

Title:

Impulse Assessment of the Enhanced Combat Helmet - Marine Corps and Five Samples of the ComTac (trademark) V Hearing Defender Headset

Descriptive Note:

[Technical Report, Technical Memo]

Corporate Author:

NAVAL SUBMARINE MEDICAL RESEARCH LAB GROTON CT

Personal Author(s):

• Kolias, Alexa H.
• Schwaller, Derek W.
• Karch, Stephanie J.
• Federman, Jeremy S.

Report Date:

2022-03-09

Pagination or Media Count:

96

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. This technical memorandum describes the IPIL testing conducted on a combined configuration that included the Gentex registered trademark Corporation Enhanced Combat Helmet Marine Corps and the ComTac trademark V Headset. Testing included two test modes for the ComTac trademark V passive and active. In all occluded conditions, the ECH-M and the ComTac trademark V were donned. Testing was completed in accordance with the ANSI standard S12.42-2010. All device samples were tested at the nominal levels of 150, 160, and 170 decibel peak dBP, re 20 mu Pa. A total of five 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. Results suggest that the ComTac trademark V Headset, when functioning properly and fitted in combination with the ECH-M can adequately protect against impulses below 166.2 dBP in the passive test mode, and 165.6 dBP in the active test mode.

Descriptors:

• united states
• department of defense
• governments
• instructions
• measurement
• test fixtures
• acquisition
• biomedical research
• data acquisition
• free field
• hearing protection
• impulse noise
• insertion loss
• marine corps
• shock tubes
• standards
• transfer functions

Subject Categories:

• Medicine and Medical Research
• Protective Equipment
• Acoustics

Distribution Statement:

[A, Approved For Public Release]