Dangerous and not dangerous frequency areas

Hearing protector attenuation,dB

Frequency, Hz
 

Hellberg hearing protection is designed to have optimal attenuation at higher frequencies where the ear is most sensitive to noise induced hearing loss (the red area).

If you are exposed to sound levels above 75 dBA, you must wear hearing protection the whole time, especially if the noise is high frequency dominated. Frequencies between 1.6 and 4 kHz are most the harmful to hearing, lower frequencies are less harmful. Scientific studies even indicate that noise below 300 Hz could protect the ear against high frequency noise. Hearing protection should be designed to
have optimum performance in the high frequency area.