SOUND ATTENUATION CHARACTERISTICS OF THE ARMY APH-5 HELMET
Abstract
An evaluation of the real-ear sound attenuation characteristics of the Army APH-5 Crash Protective Helmet was done with procedures and equipment specified by ASA Z24.22-1957. The results show that the APH-5 offers high attenuation at test frequencies 3,000 through 8,000 Hz. However, the APH-5 has relatively low sound attenuation between 75 and 2,000 Hz. In view of the poor sound attenuation characteristics of the APH-5, it was recommended that the present earmuffs be replaced with high efficiency ear protective muffs. If changing earmuffs is not feasible, it is recommended that the APH-5 be replaced by a helmet with high sound attenuation characteristics.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1967
- Accession Number
- AD0649462
Entities
People
- Robert L. Keiser
- Robert T. Camp Jr.
Organizations
- United States Army Aeromedical Research Lab