Hearing protection should have a minimum NRR of how many decibels?

• A. 10 dB
• B. 25 dB
• C. 20 dB
• D. 30 dB

Answer: (C)

NRR is the Noise Reduction Rating, which is the lab-measured amount of noise a hearing protector can reduce in decibels. For field operations like US&R, you want a baseline level of protection, and 20 dB provides that minimum attenuation to make a meaningful difference against loud tools and impacts. Real-world protection is a bit less than the lab rating because fit and seal affect effectiveness, but 20 dB still offers a practical safeguard. Ten decibels would be insufficient for typical rescue noise, while twenty-five or thirty decibels exceed the minimum needed for baseline protection.