Can hearing protector attenuation measures for impulsive noise be applied to firearm suppressors?

High-level impulse noise from small caliber firearms presents a significant risk of noise induced hearing loss (NIHL) for an unprotected ear. The most common method to reduce the level of noise is to provide hearing protection to both the shooter(s) and potential observers such as firing range instructors or interested bystanders. Not all hunters and shooters use hearing protection consistently and correctly. Firearm suppressors provide an engineering noise control that can mitigate a significant portion of the NIHL risk. There is no current industry or ANSI standard for measuring the noise reduction associated with firearm suppressors. In this study, two methods for measuring suppressor attenuation were evaluated. The first method was based on the ANSI/ASA S12.42 standard for measuring impulse peak insertion loss for hearing protection devices and modified for use with firearm suppressors. The second method was based on measuring the difference in the maximum accumulated A-weighted energy for unsuppressed and suppressed firearm impulses. The advantages and disadvantages associated with each method are discussed.