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FOAM DISPOSABLE EAR PLUGS 58426
The EPA has selected the NRR as the measure of a hearing protector's noise reducing capabilities.
Harbor Freight Tools makes no warranties as to the suitability of the NRR as a measure of actual
workplace protection since such protection is highly dependent on user training, motivation, and utilization.
A better estimate of workplace protection can be obtained by derating the labeled NRR by 50%.
The NRR calculated from this attenuation data is 32 dB. Improper fit of this device will
reduce its effectiveness in attenuating noise. Consult instructions for proper fit.
The level of noise entering a person's ear, when a hearing protector is worn as directed, is closely
approximated by the difference between the A-weighted environmental noise and the NRR.
ATTENUATION DATA ANSI S3.19-1974
Test Frequencies (Hz) 125 250 500 1000 2000 3150 4000 6300 8000 NRR
Mean Attenuation (dB) 40.6 41.6 46.8 43.3 39.4 45.3 47.6 50.0 48.6
Standard Deviation (dB) 5.7 5.8 5.2 4.6 4.5 4.8 3.4 3.2 3.3
Example:
1.) The environmental noise level as measured at the ear is 92 dBA.
2.) The NRR is 32 decibels (dB).
3.) The level of noise entering the ear is approximately equal to 60 dBA.
CAUTION! For noise environments dominated by frequencies below 500 Hz,
the C-weighted environmental noise level should be used.
The NRR used in the above example was achieved under laboratory conditions.
Although hearing protectors can be recommended for protection against harmful effects of impulsive
noise, the Noise Reduction Rating (NRR) is based on the attenuation of continuous noise and may
not be an accurate indicator of the protection attainable against impulsive noise such as gunfire.
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Wear Instructions
1. Make certain that your hands and the earplugs are clean.
2. Starting with light pressure, roll the first earplug back-and-forth
between your thumb and forefinger into a cylinder shape. Roll it as
tightly as possible. There should be no creases or folds in the earplug.
3. Once the plug is rolled, insert it into the ear canal.
You should pull on your outer ear with one hand while
you insert the plug with the other. Insert the plug into the
ear canal until it is flush with the side of your head.
4. If the earplug is uncomfortable, wait 30 seconds for the fit to
improve. The earplug will shorten as it expands. If it is still
uncomfortable, pull it out slightly, or remove, re-roll, and reinsert it.
5. Repeat the above steps for the remaining plug.
6. After both earplugs are inserted and are allowed to expand into
place, place cupped hands over both ears and compare the
sound level. With properly fitted earplugs, you should detect
little or no difference in sound level. If the one or both plugs are
not fitted properly, remove, re-roll, and reinsert the plug(s).
SAVE THESE INSTRUCTIONS.
UPC 193175439017
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