Loud noise can permanently damage your hearing. It especially affects the sounds that help you understand speech. To hear what this sounds like, try these computer-generated samples. (The sound samples are in the popular MP3 format.)

1	First, click the normal hearing link to hear a recording of a male voice reading several sentences (while this is playing, adjust your PC's volume so you can clearly understand the speaker).	Normal hearing
2	Now, click the moderate hearing loss link to hear the same recording, but altered to sound as it would for a person with a "moderate" noise-induced hearing loss.	Moderate hearing loss
3	Background noise makes speech harder to understand. Click the normal hearing with background noise link to hear the first recording again, but with a recording of a coal continuous haulage machine added to the background.	Normal hearing with background noise
4	Finally, click the moderate hearing loss with background noise link to hear the same recording again (with background noise), and with a simulated "moderate" hearing loss.	Moderate hearing loss with background noise

These hearing loss example where created using the NIOSH Hearing Loss Simulator. The Windows-based simulator displays a "control panel" for playing sounds while adjusting the simulated effects of noise and aging. The screenshot below shows the most common functions. A simulated individual's age (in years) can be entered along with the years of exposure to noise (in A-weighted decibels). The effects are shown visually on the frequency band control panel and sound level display screen while the user listens to the audio playback.