Military Operators (MOs) are exposed to a broad range of impulse noise that can vary greatly in terms of level, temporal and spectral characteristics. The accurate characterization of the performance of hearing protectors is required, to mitigate the hearing damage risk for the MOs working under such conditions. Presently, the accepted method to characterize Hearing Protection Devices (HPDs) performance is based on the measurement of the Impulse Peak Insertion Loss (IPIL); however, this measurement doesn't provide the peak Insertion Loss (IL) per Octave Band (OB). A method for measuring the peak IL per OB for HPDs was developed and is presented in this paper. The concept of an Octave Band Impulse Peak Insertion Loss (OBIPIL) is introduced to account for the HPD peak attenuation at each OB. Using a modified version of the ANSI/ASA S12.42-2010 test setup, the impulse noise signals for a 5.56 mm caliber weapon were recorded. The IPIL and the OBIPIL values of the tested HPDs were computed and are presented for comparison. Moreover, an OBIPIL comparison versus the Bone Conduction (BC) attenuation limits is provided to gauge the attenuation capabilities of each HPD at each OB. A performance behavior for each HPD is presented in the time domain and per OB. Finally, remarks, conclusions, pros and cons of the proposed methodology as well as future work are discussed.