No earplug can completely protect the user from exposure to impulse sound and in particular to gunfire or weapons fire. When properly fitted and worn will reduce exposure to harmful levels of impulse sound but cannot completely eliminate such exposure either through the ear canal or through bone conduction. Hearing loss may still occur even with proper fitting and use of any impulse noise earplug.
Properly fitted passive slow recovery foam earplugs either alone or combined with high NRR earmuffs will provide greater protection from impulse sound to the user than any reusable impulse earplug but also cannot eliminate such exposure either through the ear canal or through bone conduction.
Accordingly, hearing loss may still occur as a result of sustained or repeated exposure to impulse sound.
However, slow recovery foam earplugs, either alone or with earmuffs, will not allow the user to hear commands, approaching vehicles or other sounds the user may need to hear.